refactor(rustfs): move layer-neutral shared types out of server (#6060 )

fix(kms): teach the observing Vault deserializer the wrap-budget field
Merge race broke main: #6019 added wrap_budget_reserved to VaultKeyData (with a serde default), and #6040 — green against a base without that field — landed its unknown-field-observing manual Deserialize with an initializer that does not mention it, so rustfs-kms no longer compiles. Beyond the missing initializer field, the visitor would also have misclassified wrap_budget_reserved as an unknown field and dropped its value on every read, silently regressing the persisted wrap-budget count that #6019's whole design exists to preserve. The field is now a first-class visitor member: parsed when present, duplicate-checked, defaulting to 0 when absent (mirroring the struct's #[serde(default)] for records written before the field existed). Verification: cargo check -p rustfs-kms (fails on main, passes here); cargo test -p rustfs-kms --lib vault (178 passed); clippy --all-targets -D warnings clean.
2026-08-16 18:08:21 +00:00 · 2026-08-13 10:09:59 +08:00 · 2026-08-13 08:22:17 +08:00
233 changed files with 6902 additions and 28360 deletions
@@ -252,16 +252,10 @@ test-group = 'ecstore-serial-flaky'
 # cluster, so it keeps the lane's parallel-safe / no-external-dependency
 # properties. The RustFS warm backend has no loopback guard (that guard is
 # replication-only), so it needs no opt-in env for its 127.0.0.1 tier target.
-#
-# Disk compression (backlog#1848): the `compression` module joins the smoke
-# lane so the multipart disk-compression roundtrips (restored after
-# rustfs/rustfs#5169 disabled them) have PR-lane signal, not just merge-gate.
-# Single-node servers on random ports with isolated temp dirs — meets the
-# admission criteria unchanged.
 [profile.e2e-smoke]
 default-filter = """
    package(e2e_test) & (
-        test(/^(delete_marker_migration_semantics|version_id_regression|list_objects_v2_pagination|list_object_versions_regression|list_objects_duplicates|list_buckets_double_slash|list_buckets_auth|list_buckets_iam_filter|leading_slash_key|special_chars|create_bucket_region|delete_objects_versioning|head_object_consistency|head_object_range|copy_object_metadata|copy_object_tagging|copy_source_invalid_date|content_encoding|compression|multipart_storage_class|storage_class_capability|ssec_copy|anonymous_access|bucket_policy_check|presigned_negative|negative_sigv4|admin_auth|notification_webhook|tls_hot_reload|console_smoke|admin_iam_crud|admin_pools|sts_query_compat)_test::|^fake_s3_target::/)
+        test(/^(delete_marker_migration_semantics|version_id_regression|list_objects_v2_pagination|list_object_versions_regression|list_objects_duplicates|list_buckets_double_slash|list_buckets_auth|list_buckets_iam_filter|leading_slash_key|special_chars|create_bucket_region|delete_objects_versioning|head_object_consistency|head_object_range|copy_object_metadata|copy_object_tagging|copy_source_invalid_date|content_encoding|multipart_storage_class|storage_class_capability|ssec_copy|anonymous_access|bucket_policy_check|presigned_negative|negative_sigv4|admin_auth|notification_webhook|tls_hot_reload|console_smoke|admin_iam_crud|admin_pools|sts_query_compat)_test::|^fake_s3_target::/)
        | test(/^replication_extension_test::(test_replication_check_succeeds_with_remote_target|test_replication_check_rejects_target_without_object_lock|test_set_remote_target_rejects_unversioned_source_bucket|test_replication_check_rejects_unversioned_source_bucket|test_replication_check_rejects_missing_replication_config|test_replication_check_rejects_invalid_bucket|test_set_remote_target_rejects_same_bucket_on_same_deployment|test_set_remote_target_rejects_unversioned_target_bucket|test_set_remote_target_update_requires_arn|test_set_remote_target_update_rejects_missing_target|test_set_remote_target_rejects_invalid_target_url|test_set_remote_target_rejects_self_signed_https_target_without_skip_tls_verify|test_set_remote_target_rejects_private_ca_https_target_without_ca_cert_pem|test_list_remote_targets_rejects_empty_bucket|test_list_remote_targets_rejects_invalid_bucket|test_remove_remote_target_rejects_missing_target|test_remove_remote_target_rejects_missing_arn|test_remove_remote_target_rejects_invalid_bucket|test_remove_remote_target_rejects_target_used_by_replication|test_delete_bucket_replication_removes_remote_target)$/)
        | test(/^reliant::lifecycle::/)
        | test(/^reliant::tiering::/)
@@ -182,12 +182,7 @@ jobs:
            echo '```'
          } >> "$GITHUB_STEP_SUMMARY"

-  # Readers: test-and-lint-rio-v2 (per-PR), build-rustfs-debug-binary-rio-v2
-  # (weekly schedule / manual dispatch only — dormant rio-v2 variant, see
-  # rustfs/backlog#1835 and docs/architecture/minio-file-format-compat.md).
-  # The second build below stays despite the reduced cadence: it warms the
-  # rio-v2,e2e-test-hooks feature resolution the scheduled build restores,
-  # which keeps that lane inside its 30-minute timeout.
+  # Readers: test-and-lint-rio-v2, build-rustfs-debug-binary-rio-v2.
  warm-ci-feat-rio:
    name: Warm ci-feat-rio
    runs-on: sm-standard-4
@@ -533,12 +533,7 @@ jobs:

  build-rustfs-debug-binary-rio-v2:
    name: Build RustFS Debug Binary (rio-v2)
-    # Dormant rio-v2 variant (rustfs/backlog#1835): the feature ships in no
-    # default build, so this full-suite lane runs only on the weekly schedule
-    # and manual dispatch. Per-PR cfg-seam coverage stays with
-    # test-and-lint-rio-v2. Lifecycle and the promote-or-delete condition:
-    # docs/architecture/minio-file-format-compat.md ("rio-v2 variant lifecycle").
-    if: github.event_name == 'schedule' || github.event_name == 'workflow_dispatch'
+    if: github.event_name != 'pull_request' || github.event.action != 'closed'
    needs: [ quick-checks ]
    runs-on: sm-standard-4
    timeout-minutes: 30
@@ -829,9 +824,6 @@ jobs:

  e2e-tests-rio-v2:
    name: End-to-End Tests (rio-v2)
-    # Inherits the schedule/dispatch-only gate through needs: on every other
-    # event build-rustfs-debug-binary-rio-v2 is skipped, so this job skips
-    # with it (see the dormant-variant comment on that job).
    needs: [ build-rustfs-debug-binary-rio-v2 ]
    runs-on: sm-standard-2
    timeout-minutes: 30
@@ -94,7 +94,6 @@ jobs:
      short_sha: ${{ steps.check.outputs.short_sha }}
      is_prerelease: ${{ steps.check.outputs.is_prerelease }}
      create_latest: ${{ steps.check.outputs.create_latest }}
-      source_ref: ${{ steps.check.outputs.source_ref }}
    steps:
      - name: Checkout repository
        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
@@ -119,7 +118,6 @@ jobs:
          short_sha=""
          is_prerelease=false
          create_latest=false
-          source_ref="$GITHUB_SHA"

          if [[ "${{ github.event_name }}" == "workflow_run" ]]; then
            # Triggered by build workflow completion
@@ -139,7 +137,6 @@ jobs:
            # Extract version info from commit message or use commit SHA
            # Use Git to generate consistent short SHA (ensures uniqueness like build.yml)
            short_sha=$(git rev-parse --short "$HEAD_SHA")
-            source_ref="$HEAD_SHA"

            # Determine build type based on triggering workflow event and ref
            triggering_event="$TRIGGERING_EVENT"
@@ -264,23 +261,6 @@ jobs:
                echo "⚠️  Only release versions (latest, v1.0.0, 1.0.0) and prereleases (v1.0.0-alpha1, 1.0.0-beta2) are supported"
                ;;
            esac
-
-            if [[ "$should_build" == true && "$input_version" != "latest" ]]; then
-              tag_ref="refs/tags/$input_version"
-              if ! git ls-remote --exit-code origin "$tag_ref" >/dev/null 2>&1; then
-                if [[ "$input_version" == v* ]]; then
-                  tag_ref="refs/tags/${input_version#v}"
-                else
-                  tag_ref="refs/tags/v$input_version"
-                fi
-              fi
-
-              if ! git ls-remote --exit-code origin "$tag_ref" >/dev/null 2>&1; then
-                echo "❌ Release tag not found for Docker build: $input_version"
-                exit 1
-              fi
-              source_ref="$tag_ref"
-            fi
          fi

          {
@@ -291,7 +271,6 @@ jobs:
            echo "short_sha=$short_sha"
            echo "is_prerelease=$is_prerelease"
            echo "create_latest=$create_latest"
-            echo "source_ref=$source_ref"
          } >> "$GITHUB_OUTPUT"

          echo "🐳 Docker Build Summary:"
@@ -302,7 +281,6 @@ jobs:
          echo "  - Short SHA: $short_sha"
          echo "  - Is prerelease: $is_prerelease"
          echo "  - Create latest: $create_latest"
-          echo "  - Source ref: $source_ref"

  # Build multi-arch Docker images
  # Strategy: Build images using pre-built binaries from dl.rustfs.com
@@ -330,7 +308,6 @@ jobs:
        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
        with:
          persist-credentials: false
-          ref: ${{ needs.build-check.outputs.source_ref }}

      - name: Login to Docker Hub
        uses: docker/login-action@c94ce9fb468520275223c153574b00df6fe4bcc9 # v3
@@ -420,8 +397,7 @@ jobs:
          LABELS="org.opencontainers.image.title=RustFS"
          LABELS="$LABELS,org.opencontainers.image.description=RustFS distributed object storage system"
          LABELS="$LABELS,org.opencontainers.image.version=$VERSION"
-          SOURCE_REVISION="$(git rev-parse HEAD)"
-          LABELS="$LABELS,org.opencontainers.image.revision=$SOURCE_REVISION"
+          LABELS="$LABELS,org.opencontainers.image.revision=${{ github.sha }}"
          LABELS="$LABELS,org.opencontainers.image.source=${{ github.server_url }}/${{ github.repository }}"
          LABELS="$LABELS,org.opencontainers.image.created=$(date -u +'%Y-%m-%dT%H:%M:%SZ')"
          LABELS="$LABELS,org.opencontainers.image.build-type=$BUILD_TYPE"
@@ -101,10 +101,7 @@ refactors.

 The `rustfs` binary crate composes these libraries into the running server.
 `ecstore` remains the storage engine at the architectural center; its internal
-module split is tracked under `docs/architecture/`. `rio-v2` is the
-feature-gated MinIO on-disk format compatibility I/O layer; it ships in no
-default build (lifecycle:
-[docs/architecture/minio-file-format-compat.md](docs/architecture/minio-file-format-compat.md)).
+module split is tracked under `docs/architecture/`.

 ## Architecture Invariants

@@ -1162,9 +1162,9 @@ dependencies = [

 [[package]]
 name = "aws-smithy-eventstream"
-version = "0.61.2"
+version = "0.61.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6de526c7b567420a31bc283657a7921b45c4cafe0827fdf2490713dcc770c28f"
+checksum = "5a9381123ab62d20c13082b151f30f962a3b112b727345394536dfa39a482944"
 dependencies = [
 "aws-smithy-types",
 "bytes",
@@ -1195,9 +1195,9 @@ dependencies = [

 [[package]]
 name = "aws-smithy-http-client"
-version = "1.3.0"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3c1c8a04cb31ba74d0115af5a890bb8c0d48fba64b52812fa13929a6ef0cc83c"
+checksum = "635d23afda0a6ab48d666c4d447c4873e8d1e83518a2be2093122397e50b838e"
 dependencies = [
 "aws-smithy-async",
 "aws-smithy-protocol-test",
@@ -1277,9 +1277,9 @@ dependencies = [

 [[package]]
 name = "aws-smithy-runtime"
-version = "1.13.1"
+version = "1.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "483b858ff67522011c4786310c5cd8fd88d0be7ea3d5f1a48328446300c4269e"
+checksum = "07505b34e8f4b3591a4fa69e9792b52289b95488dbbc68c3c0075b7bedb245e1"
 dependencies = [
 "aws-smithy-async",
 "aws-smithy-http",
@@ -1343,9 +1343,9 @@ dependencies = [

 [[package]]
 name = "aws-smithy-types"
-version = "1.6.2"
+version = "1.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fce83ce9abbb198d25bc7131e468d0f9fe1257125e58c39f3f9fc9f5098c9647"
+checksum = "d6dc683efb34b9e755675b37fedbe0103141e5b6df7bdc9eb6967756a8c167d8"
 dependencies = [
 "base64-simd",
 "bytes",
@@ -3761,7 +3761,7 @@ checksum = "d0881ea181b1df73ff77ffaaf9c7544ecc11e82fba9b5f27b262a3c73a332555"

 [[package]]
 name = "e2e_test"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "anyhow",
 "astral-tokio-tar",
@@ -5133,9 +5133,9 @@ dependencies = [

 [[package]]
 name = "http-body-util"
-version = "0.1.5"
+version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "23169fe34a5fbcdd3f3862e78fb9b6fccd5f02a6dc6f732547005d45631ce71c"
+checksum = "e9f41fd6a08e4d4ec69df65976da761afd5ad5e58a9d4acb46bd1c953a9e3ff2"
 dependencies = [
 "bytes",
 "futures-core",
@@ -5957,7 +5957,7 @@ checksum = "b6d2cec3eae94f9f509c767b45932f1ada8350c4bdb85af2fcab4a3c14807981"
 [[package]]
 name = "libmimalloc-sys"
 version = "0.1.49"
-source = "git+https://github.com/xonatius/mimalloc_rust.git?rev=6d4c41bb10c6d9da1d1b6f07b38c4cc051667f11#6d4c41bb10c6d9da1d1b6f07b38c4cc051667f11"
+source = "git+https://github.com/xonatius/mimalloc_rust.git?rev=ce6338661179c8be22e516b00af7483f151485a7#ce6338661179c8be22e516b00af7483f151485a7"
 dependencies = [
 "cc",
 "cty",
@@ -6259,9 +6259,9 @@ dependencies = [

 [[package]]
 name = "metrique"
-version = "0.1.30"
+version = "0.1.29"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dedbf06ffeef4c37990c73636fbd993aa34fb1948afd736e6114f239220993db"
+checksum = "d2e394c63e2d1a30aeb3b9392ecf3439d8475d2df810a8f4f6e66d6866754017"
 dependencies = [
 "itoa",
 "jiff",
@@ -6289,9 +6289,9 @@ dependencies = [

 [[package]]
 name = "metrique-macro"
-version = "0.1.21"
+version = "0.1.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f4fb1f30185f53f7f6e4c9e46745c1a1350af8e77fda5a88aded44b0637a82e0"
+checksum = "786df1fd0abebd0db685f7e9a353c78756d4b370fb98a52376c2015fa55f141f"
 dependencies = [
 "Inflector",
 "darling 0.23.0",
@@ -6318,9 +6318,9 @@ checksum = "2faca4e4480069ff02b1763b3b79f5cec7e8628e24d9dc5b6073f53d2577a4d9"

 [[package]]
 name = "metrique-writer"
-version = "0.1.26"
+version = "0.1.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "20bd17c1a3ca2719e31f19ce77a853948dc2102f35976b92276c42a64fdc5f3f"
+checksum = "82cdde44d241dab7fc8b7a32e0eb5dae6cd28f8de80b59f9a1e9f2f0b05e485e"
 dependencies = [
 "ahash",
 "crossbeam-queue",
@@ -6339,9 +6339,9 @@ dependencies = [

 [[package]]
 name = "metrique-writer-core"
-version = "0.1.20"
+version = "0.1.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f1a55b6aae1d85c557c729564c4e2b32a26dc65ba2d90d9647ca01f2bd4854c4"
+checksum = "e57379b7ee2272efaeaaa6de062503563e57333b24aadc7f2255b3d602899e8b"
 dependencies = [
 "derive-where",
 "itertools 0.14.0",
@@ -6366,7 +6366,7 @@ dependencies = [
 [[package]]
 name = "mimalloc"
 version = "0.1.52"
-source = "git+https://github.com/xonatius/mimalloc_rust.git?rev=6d4c41bb10c6d9da1d1b6f07b38c4cc051667f11#6d4c41bb10c6d9da1d1b6f07b38c4cc051667f11"
+source = "git+https://github.com/xonatius/mimalloc_rust.git?rev=ce6338661179c8be22e516b00af7483f151485a7#ce6338661179c8be22e516b00af7483f151485a7"
 dependencies = [
 "libmimalloc-sys",
 ]
@@ -6882,7 +6882,7 @@ version = "5.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "51e219e79014df21a225b1860a479e2dcd7cbd9130f4defd4bd0e191ea31d67d"
 dependencies = [
- "base64 0.21.7",
+ "base64 0.22.1",
 "chrono",
 "getrandom 0.2.17",
 "http 1.5.0",
@@ -8043,7 +8043,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "be769465445e8c1474e9c5dac2018218498557af32d9ed057325ec9a41ae81bf"
 dependencies = [
 "heck 0.5.0",
- "itertools 0.10.5",
+ "itertools 0.14.0",
 "log",
 "multimap",
 "once_cell",
@@ -8063,7 +8063,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "03da047801ff44bb6a4d407d4860c05fd70bb81714e6b2f3812603d5b145b042"
 dependencies = [
 "heck 0.5.0",
- "itertools 0.10.5",
+ "itertools 0.14.0",
 "log",
 "multimap",
 "petgraph 0.8.3",
@@ -8084,7 +8084,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8a56d757972c98b346a9b766e3f02746cde6dd1cd1d1d563472929fdd74bec4d"
 dependencies = [
 "anyhow",
- "itertools 0.10.5",
+ "itertools 0.14.0",
 "proc-macro2",
 "quote",
 "syn 2.0.119",
@@ -8097,7 +8097,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b570b25f7617e43d59005d0990ccb79e950a423952cea19671b7a876da390adf"
 dependencies = [
 "anyhow",
- "itertools 0.10.5",
+ "itertools 0.14.0",
 "proc-macro2",
 "quote",
 "syn 2.0.119",
@@ -9090,7 +9090,7 @@ dependencies = [

 [[package]]
 name = "rustfs"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "aes-gcm",
 "anyhow",
@@ -9227,7 +9227,7 @@ dependencies = [

 [[package]]
 name = "rustfs-audit"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "async-trait",
 "const-str",
@@ -9250,7 +9250,7 @@ dependencies = [

 [[package]]
 name = "rustfs-checksums"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "base64-simd",
 "bytes",
@@ -9266,7 +9266,7 @@ dependencies = [

 [[package]]
 name = "rustfs-common"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "chrono",
 "hotpath",
@@ -9284,7 +9284,7 @@ dependencies = [

 [[package]]
 name = "rustfs-concurrency"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "hotpath",
 "insta",
@@ -9297,7 +9297,7 @@ dependencies = [

 [[package]]
 name = "rustfs-config"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "const-str",
 "hotpath",
@@ -9307,7 +9307,7 @@ dependencies = [

 [[package]]
 name = "rustfs-credentials"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "base64-simd",
 "hmac 0.13.0",
@@ -9321,7 +9321,7 @@ dependencies = [

 [[package]]
 name = "rustfs-crypto"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "aes-gcm",
 "argon2",
@@ -9342,7 +9342,7 @@ dependencies = [

 [[package]]
 name = "rustfs-data-usage"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "hotpath",
 "rmp-serde",
@@ -9352,7 +9352,7 @@ dependencies = [

 [[package]]
 name = "rustfs-ecstore"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "arc-swap",
 "async-channel",
@@ -9491,7 +9491,7 @@ dependencies = [

 [[package]]
 name = "rustfs-extension-schema"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "hotpath",
 "serde",
@@ -9501,7 +9501,7 @@ dependencies = [

 [[package]]
 name = "rustfs-filemeta"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "arc-swap",
 "byteorder",
@@ -9528,7 +9528,7 @@ dependencies = [

 [[package]]
 name = "rustfs-heal"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "async-trait",
 "base64 0.23.1",
@@ -9559,7 +9559,7 @@ dependencies = [

 [[package]]
 name = "rustfs-iam"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "arc-swap",
 "async-trait",
@@ -9600,7 +9600,7 @@ dependencies = [

 [[package]]
 name = "rustfs-io-core"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "bytes",
 "hotpath",
@@ -9613,14 +9613,16 @@ dependencies = [

 [[package]]
 name = "rustfs-io-metrics"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "criterion",
 "hotpath",
 "metrics",
 "metrics-util",
 "num_cpus",
+ "rustfs-common",
 "rustfs-s3-ops",
+ "rustfs-utils",
 "sysinfo",
 "thiserror 2.0.20",
 "tokio",
@@ -9677,7 +9679,7 @@ dependencies = [

 [[package]]
 name = "rustfs-keystone"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "bytes",
 "futures",
@@ -9704,7 +9706,7 @@ dependencies = [

 [[package]]
 name = "rustfs-kms"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "aes-gcm",
 "anyhow",
@@ -9753,7 +9755,7 @@ dependencies = [

 [[package]]
 name = "rustfs-lifecycle"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "async-trait",
 "hotpath",
@@ -9776,7 +9778,7 @@ dependencies = [

 [[package]]
 name = "rustfs-lock"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "async-trait",
 "compact_str",
@@ -9799,7 +9801,7 @@ dependencies = [

 [[package]]
 name = "rustfs-log-analyzer"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "chrono",
 "flate2",
@@ -9818,7 +9820,7 @@ dependencies = [

 [[package]]
 name = "rustfs-madmin"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "hotpath",
 "humantime",
@@ -9833,7 +9835,7 @@ dependencies = [

 [[package]]
 name = "rustfs-notify"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "arc-swap",
 "async-trait",
@@ -9868,7 +9870,7 @@ dependencies = [

 [[package]]
 name = "rustfs-object-capacity"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "criterion",
 "futures",
@@ -9888,7 +9890,7 @@ dependencies = [

 [[package]]
 name = "rustfs-object-data-cache"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "bytes",
 "criterion",
@@ -9905,7 +9907,7 @@ dependencies = [

 [[package]]
 name = "rustfs-obs"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "chrono",
 "crossbeam-channel",
@@ -9960,7 +9962,7 @@ dependencies = [

 [[package]]
 name = "rustfs-policy"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "async-trait",
 "base64-simd",
@@ -9991,7 +9993,7 @@ dependencies = [

 [[package]]
 name = "rustfs-protocols"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "astral-tokio-tar",
 "async-compression",
@@ -10053,7 +10055,7 @@ dependencies = [

 [[package]]
 name = "rustfs-protos"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "flatbuffers",
 "hotpath",
@@ -10077,7 +10079,7 @@ dependencies = [

 [[package]]
 name = "rustfs-replication"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "byteorder",
 "bytes",
@@ -10095,7 +10097,7 @@ dependencies = [

 [[package]]
 name = "rustfs-rio"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "aes-gcm",
 "arc-swap",
@@ -10133,7 +10135,7 @@ dependencies = [

 [[package]]
 name = "rustfs-rio-v2"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "aes-gcm",
 "bytes",
@@ -10156,7 +10158,7 @@ dependencies = [

 [[package]]
 name = "rustfs-s3-ops"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "hotpath",
 "rustfs-s3-types",
@@ -10164,7 +10166,7 @@ dependencies = [

 [[package]]
 name = "rustfs-s3-types"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "hotpath",
 "serde",
@@ -10173,7 +10175,7 @@ dependencies = [

 [[package]]
 name = "rustfs-s3select-api"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "async-trait",
 "bytes",
@@ -10203,7 +10205,7 @@ dependencies = [

 [[package]]
 name = "rustfs-s3select-query"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "async-recursion",
 "async-trait",
@@ -10222,7 +10224,7 @@ dependencies = [

 [[package]]
 name = "rustfs-scanner"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "async-trait",
 "bytes",
@@ -10262,7 +10264,7 @@ dependencies = [

 [[package]]
 name = "rustfs-security-governance"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "hotpath",
 "thiserror 2.0.20",
@@ -10270,7 +10272,7 @@ dependencies = [

 [[package]]
 name = "rustfs-signer"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "base64-simd",
 "bytes",
@@ -10288,7 +10290,7 @@ dependencies = [

 [[package]]
 name = "rustfs-storage-api"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "async-trait",
 "hotpath",
@@ -10303,7 +10305,7 @@ dependencies = [

 [[package]]
 name = "rustfs-targets"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "arc-swap",
 "async-nats",
@@ -10357,7 +10359,7 @@ dependencies = [

 [[package]]
 name = "rustfs-test-utils"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "hotpath",
 "rustfs-data-usage",
@@ -10373,7 +10375,7 @@ dependencies = [

 [[package]]
 name = "rustfs-tls-runtime"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "arc-swap",
 "hotpath",
@@ -10394,7 +10396,7 @@ dependencies = [

 [[package]]
 name = "rustfs-trusted-proxies"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "async-trait",
 "axum",
@@ -10431,7 +10433,7 @@ dependencies = [

 [[package]]
 name = "rustfs-utils"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "base64-simd",
 "blake2",
@@ -10473,7 +10475,7 @@ dependencies = [

 [[package]]
 name = "rustfs-zip"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 dependencies = [
 "astral-tokio-tar",
 "async-compression",
@@ -10559,9 +10561,9 @@ dependencies = [

 [[package]]
 name = "rustls-connector"
-version = "0.23.8"
+version = "0.23.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1babecfcc65b139b812e74bcc7f9ec7b4e00db659fd42d99567b7e77f0c714c6"
+checksum = "09a5abe04eec18f8b9fbe87885bcaee6426de80bbc579958c0bc064b728ee617"
 dependencies = [
 "futures-io",
 "futures-rustls",
@@ -11800,7 +11802,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "32497e9a4c7b38532efcdebeef879707aa9f794296a4f0244f6f69e9bc8574bd"
 dependencies = [
 "fastrand",
- "getrandom 0.3.4",
+ "getrandom 0.4.3",
 "once_cell",
 "rustix",
 "windows-sys 0.61.2",
@@ -41,7 +41,7 @@ members = [
    "crates/protocols", # Protocol implementations (FTPS, SFTP, etc.)
    "crates/protos", # Protocol buffer definitions
    "crates/rio", # Rust I/O utilities and abstractions
-    "crates/rio-v2", # MinIO on-disk format compatibility I/O layer (feature-gated, ships in no default build)
+    "crates/rio-v2", # Next-generation Rust I/O compatibility layer
    "crates/replication", # Replication contracts and wire formats
    "crates/concurrency", # Concurrency management for RustFS - timeout, locking, backpressure, and I/O scheduling
    "crates/s3-types", # S3 event type definitions
@@ -69,7 +69,7 @@ edition = "2024"
 license = "Apache-2.0"
 repository = "https://github.com/rustfs/rustfs"
 rust-version = "1.97.1"
-version = "1.0.0-rc.2"
+version = "1.0.0-rc.1"
 homepage = "https://rustfs.com"
 description = "RustFS is a high-performance distributed object storage software built using Rust, one of the most popular languages worldwide. "
 keywords = ["RustFS", "Minio", "object-storage", "filesystem", "s3"]
@@ -86,52 +86,52 @@ redundant_clone = "warn"

 [workspace.dependencies]
 # RustFS Internal Crates
-rustfs = { path = "./rustfs", version = "1.0.0-rc.2" }
-rustfs-heal = { path = "crates/heal", version = "1.0.0-rc.2" }
-rustfs-audit = { path = "crates/audit", version = "1.0.0-rc.2" }
-rustfs-checksums = { path = "crates/checksums", version = "1.0.0-rc.2" }
-rustfs-common = { path = "crates/common", version = "1.0.0-rc.2" }
-rustfs-data-usage = { path = "crates/data-usage", version = "1.0.0-rc.2" }
-rustfs-config = { path = "./crates/config", version = "1.0.0-rc.2" }
-rustfs-concurrency = { path = "./crates/concurrency", version = "1.0.0-rc.2" }
-rustfs-credentials = { path = "crates/credentials", version = "1.0.0-rc.2" }
-rustfs-crypto = { path = "crates/crypto", version = "1.0.0-rc.2" }
-rustfs-ecstore = { path = "crates/ecstore", version = "1.0.0-rc.2" }
-rustfs-filemeta = { path = "crates/filemeta", version = "1.0.0-rc.2" }
-rustfs-iam = { path = "crates/iam", version = "1.0.0-rc.2" }
-rustfs-keystone = { path = "crates/keystone", version = "1.0.0-rc.2" }
-rustfs-lifecycle = { path = "crates/lifecycle", version = "1.0.0-rc.2" }
-rustfs-kms = { path = "crates/kms", version = "1.0.0-rc.2" }
-rustfs-lock = { path = "crates/lock", version = "1.0.0-rc.2" }
-rustfs-madmin = { path = "crates/madmin", version = "1.0.0-rc.2" }
-rustfs-notify = { path = "crates/notify", version = "1.0.0-rc.2" }
-rustfs-io-metrics = { path = "crates/io-metrics", version = "1.0.0-rc.2" }
-rustfs-io-core = { path = "crates/io-core", version = "1.0.0-rc.2" }
-rustfs-object-capacity = { path = "crates/object-capacity", version = "1.0.0-rc.2" }
-rustfs-object-data-cache = { path = "crates/object-data-cache", version = "1.0.0-rc.2", default-features = false }
-rustfs-log-analyzer = { path = "crates/log-analyzer", version = "1.0.0-rc.2" }
-rustfs-obs = { path = "crates/obs", version = "1.0.0-rc.2" }
-rustfs-policy = { path = "crates/policy", version = "1.0.0-rc.2" }
-rustfs-protos = { path = "crates/protos", version = "1.0.0-rc.2" }
-rustfs-protocols = { path = "crates/protocols", version = "1.0.0-rc.2" }
-rustfs-replication = { path = "crates/replication", version = "1.0.0-rc.2" }
-rustfs-rio = { path = "crates/rio", version = "1.0.0-rc.2" }
-rustfs-rio-v2 = { path = "crates/rio-v2", version = "1.0.0-rc.2" }
-rustfs-s3-types = { path = "crates/s3-types", version = "1.0.0-rc.2" }
-rustfs-s3-ops = { path = "crates/s3-ops", version = "1.0.0-rc.2" }
-rustfs-s3select-api = { path = "crates/s3select-api", version = "1.0.0-rc.2" }
-rustfs-s3select-query = { path = "crates/s3select-query", version = "1.0.0-rc.2" }
-rustfs-scanner = { path = "crates/scanner", version = "1.0.0-rc.2" }
-rustfs-security-governance = { path = "crates/security-governance", version = "1.0.0-rc.2" }
-rustfs-extension-schema = { path = "crates/extension-schema", version = "1.0.0-rc.2" }
-rustfs-signer = { path = "crates/signer", version = "1.0.0-rc.2" }
-rustfs-storage-api = { path = "crates/storage-api", version = "1.0.0-rc.2" }
-rustfs-trusted-proxies = { path = "crates/trusted-proxies", version = "1.0.0-rc.2" }
-rustfs-targets = { path = "crates/targets", version = "1.0.0-rc.2" }
-rustfs-test-utils = { path = "crates/test-utils", version = "1.0.0-rc.2" }
-rustfs-tls-runtime = { path = "crates/tls-runtime", version = "1.0.0-rc.2" }
-rustfs-utils = { path = "crates/utils", version = "1.0.0-rc.2" }
-rustfs-zip = { path = "./crates/zip", version = "1.0.0-rc.2" }
+rustfs = { path = "./rustfs", version = "1.0.0-rc.1" }
+rustfs-heal = { path = "crates/heal", version = "1.0.0-rc.1" }
+rustfs-audit = { path = "crates/audit", version = "1.0.0-rc.1" }
+rustfs-checksums = { path = "crates/checksums", version = "1.0.0-rc.1" }
+rustfs-common = { path = "crates/common", version = "1.0.0-rc.1" }
+rustfs-data-usage = { path = "crates/data-usage", version = "1.0.0-rc.1" }
+rustfs-config = { path = "./crates/config", version = "1.0.0-rc.1" }
+rustfs-concurrency = { path = "./crates/concurrency", version = "1.0.0-rc.1" }
+rustfs-credentials = { path = "crates/credentials", version = "1.0.0-rc.1" }
+rustfs-crypto = { path = "crates/crypto", version = "1.0.0-rc.1" }
+rustfs-ecstore = { path = "crates/ecstore", version = "1.0.0-rc.1" }
+rustfs-filemeta = { path = "crates/filemeta", version = "1.0.0-rc.1" }
+rustfs-iam = { path = "crates/iam", version = "1.0.0-rc.1" }
+rustfs-keystone = { path = "crates/keystone", version = "1.0.0-rc.1" }
+rustfs-lifecycle = { path = "crates/lifecycle", version = "1.0.0-rc.1" }
+rustfs-kms = { path = "crates/kms", version = "1.0.0-rc.1" }
+rustfs-lock = { path = "crates/lock", version = "1.0.0-rc.1" }
+rustfs-madmin = { path = "crates/madmin", version = "1.0.0-rc.1" }
+rustfs-notify = { path = "crates/notify", version = "1.0.0-rc.1" }
+rustfs-io-metrics = { path = "crates/io-metrics", version = "1.0.0-rc.1" }
+rustfs-io-core = { path = "crates/io-core", version = "1.0.0-rc.1" }
+rustfs-object-capacity = { path = "crates/object-capacity", version = "1.0.0-rc.1" }
+rustfs-object-data-cache = { path = "crates/object-data-cache", version = "1.0.0-rc.1", default-features = false }
+rustfs-log-analyzer = { path = "crates/log-analyzer", version = "1.0.0-rc.1" }
+rustfs-obs = { path = "crates/obs", version = "1.0.0-rc.1" }
+rustfs-policy = { path = "crates/policy", version = "1.0.0-rc.1" }
+rustfs-protos = { path = "crates/protos", version = "1.0.0-rc.1" }
+rustfs-protocols = { path = "crates/protocols", version = "1.0.0-rc.1" }
+rustfs-replication = { path = "crates/replication", version = "1.0.0-rc.1" }
+rustfs-rio = { path = "crates/rio", version = "1.0.0-rc.1" }
+rustfs-rio-v2 = { path = "crates/rio-v2", version = "1.0.0-rc.1" }
+rustfs-s3-types = { path = "crates/s3-types", version = "1.0.0-rc.1" }
+rustfs-s3-ops = { path = "crates/s3-ops", version = "1.0.0-rc.1" }
+rustfs-s3select-api = { path = "crates/s3select-api", version = "1.0.0-rc.1" }
+rustfs-s3select-query = { path = "crates/s3select-query", version = "1.0.0-rc.1" }
+rustfs-scanner = { path = "crates/scanner", version = "1.0.0-rc.1" }
+rustfs-security-governance = { path = "crates/security-governance", version = "1.0.0-rc.1" }
+rustfs-extension-schema = { path = "crates/extension-schema", version = "1.0.0-rc.1" }
+rustfs-signer = { path = "crates/signer", version = "1.0.0-rc.1" }
+rustfs-storage-api = { path = "crates/storage-api", version = "1.0.0-rc.1" }
+rustfs-trusted-proxies = { path = "crates/trusted-proxies", version = "1.0.0-rc.1" }
+rustfs-targets = { path = "crates/targets", version = "1.0.0-rc.1" }
+rustfs-test-utils = { path = "crates/test-utils", version = "1.0.0-rc.1" }
+rustfs-tls-runtime = { path = "crates/tls-runtime", version = "1.0.0-rc.1" }
+rustfs-utils = { path = "crates/utils", version = "1.0.0-rc.1" }
+rustfs-zip = { path = "./crates/zip", version = "1.0.0-rc.1" }

 # Async Runtime and Networking
 async-channel = "2.5.0"
@@ -154,7 +154,7 @@ hyper-rustls = { default-features = false, version = "0.27.9" }
 hyper-util = { version = "0.1.20" }
 http = "1.5.0"
 http-body = "1.1.0"
-http-body-util = "0.1.5"
+http-body-util = "0.1.4"
 minlz = "1.2.3"
 reqwest = "0.13.4"
 rustfs-kafka-async = { version = "1.2.0" }
@@ -231,9 +231,9 @@ aws-credential-types = { version = "1.3.0" }
 aws-sdk-kms = { default-features = false, version = "1.114.0" }
 aws-sdk-s3 = { default-features = false, version = "1.141.0" }
 aws-sdk-sts = { default-features = false, version = "1.110.0" }
-aws-smithy-http-client = { default-features = false, version = "1.3.0" }
+aws-smithy-http-client = { default-features = false, version = "1.2.0" }
 aws-smithy-runtime-api = { version = "1.14.0" }
-aws-smithy-types = { version = "1.6.2" }
+aws-smithy-types = { version = "1.6.1" }
 base64 = "0.23.1"
 base64-simd = "0.8.0"
 brotli = "8.0.4"
@@ -348,8 +348,8 @@ russh-sftp = "2.4.0"
 dav-server = "0.11.0"

 # Performance Analysis and Memory Profiling
-mimalloc = { version = "0.1.52", git = "https://github.com/xonatius/mimalloc_rust.git", rev = "6d4c41bb10c6d9da1d1b6f07b38c4cc051667f11" }
-libmimalloc-sys = { version = "0.1.49", git = "https://github.com/xonatius/mimalloc_rust.git", rev = "6d4c41bb10c6d9da1d1b6f07b38c4cc051667f11", features = ["extended"] }
+mimalloc = { version = "0.1.52", git = "https://github.com/xonatius/mimalloc_rust.git", rev = "ce6338661179c8be22e516b00af7483f151485a7" }
+libmimalloc-sys = { version = "0.1.49", git = "https://github.com/xonatius/mimalloc_rust.git", rev = "ce6338661179c8be22e516b00af7483f151485a7", features = ["extended"] }
 hotpath = { version = "0.23.2", default-features = false }
 # Snapshot testing for output format regression detection
 insta = { version = "1.48" }
@@ -116,7 +116,7 @@ chown -R 10001:10001 data logs
 docker run -d -p 9000:9000 -p 9001:9001 -v $(pwd)/data:/data -v $(pwd)/logs:/logs rustfs/rustfs:latest

 # Using specific version
-docker run -d -p 9000:9000 -p 9001:9001 -v $(pwd)/data:/data -v $(pwd)/logs:/logs rustfs/rustfs:1.0.0-rc.2
+docker run -d -p 9000:9000 -p 9001:9001 -v $(pwd)/data:/data -v $(pwd)/logs:/logs rustfs/rustfs:1.0.0-rc.1
 ```

 If you use [podman](https://github.com/containers/podman) instead of docker, you can install the RustFS with the below command
@@ -113,7 +113,7 @@ chown -R 10001:10001 data logs
 docker run -d -p 9000:9000 -p 9001:9001 -v $(pwd)/data:/data -v $(pwd)/logs:/logs rustfs/rustfs:latest

 # 使用指定版本运行
-docker run -d -p 9000:9000 -p 9001:9001 -v $(pwd)/data:/data -v $(pwd)/logs:/logs rustfs/rustfs:1.0.0-rc.2
+docker run -d -p 9000:9000 -p 9001:9001 -v $(pwd)/data:/data -v $(pwd)/logs:/logs rustfs/rustfs:1.0.0-rc.1
 ```

 如果您通过绑定挂载启用 TLS 证书目录，也请用同样方式准备该目录：
@@ -353,11 +353,6 @@ pub const DEFAULT_OBS_TRACES_EXPORT_ENABLED: bool = true;
 /// Environment variable: RUSTFS_OBS_METRICS_EXPORT_ENABLED
 pub const DEFAULT_OBS_METRICS_EXPORT_ENABLED: bool = true;

-/// Default detailed PUT stage metrics enabled
-/// Default value: false
-/// Environment variable: RUSTFS_OBS_PUT_STAGE_METRICS_ENABLED
-pub const DEFAULT_OBS_PUT_STAGE_METRICS_ENABLED: bool = false;
-
 /// Default logs export enabled
 /// It is used to enable or disable exporting logs
 /// Default value: true
@@ -137,37 +137,6 @@ pub const DEFAULT_TIER_REMOTE_VERSION_STATE_FLEET_CONFIRMED: bool = false;
 const _: () = assert!(!DEFAULT_TIER_REMOTE_VERSION_STATE_WRITE);
 const _: () = assert!(!DEFAULT_TIER_REMOTE_VERSION_STATE_FLEET_CONFIRMED);

-/// Request the object-transaction fencing contract used by storage-owned
-/// cleanup receipts and lock-window optimizations.
-///
-/// This is fail-closed: enabling the writer without a live fleet proof rejects
-/// the commit rather than silently using a legacy-safe path.
-pub const ENV_OBJECT_TRANSACTION_FENCING_WRITE: &str = "RUSTFS_OBJECT_TRANSACTION_FENCING_WRITE";
-pub const DEFAULT_OBJECT_TRANSACTION_FENCING_WRITE: bool = false;
-
-/// Operator-attested confirmation that every serving node understands the
-/// object transaction fencing contract.
-pub const ENV_OBJECT_TRANSACTION_FENCING_FLEET_CONFIRMED: &str = "RUSTFS_OBJECT_TRANSACTION_FENCING_FLEET_CONFIRMED";
-pub const DEFAULT_OBJECT_TRANSACTION_FENCING_FLEET_CONFIRMED: bool = false;
-
-const _: () = assert!(!DEFAULT_OBJECT_TRANSACTION_FENCING_WRITE);
-const _: () = assert!(!DEFAULT_OBJECT_TRANSACTION_FENCING_FLEET_CONFIRMED);
-
-/// Request preserving legacy per-part checksum metadata during data movement.
-///
-/// This remains ineffective until
-/// [`ENV_DATA_MOVEMENT_PART_CHECKSUMS_FLEET_CONFIRMED`] is also enabled.
-pub const ENV_DATA_MOVEMENT_PART_CHECKSUMS_WRITE: &str = "RUSTFS_DATA_MOVEMENT_PART_CHECKSUMS_WRITE";
-pub const DEFAULT_DATA_MOVEMENT_PART_CHECKSUMS_WRITE: bool = false;
-
-/// Operator-attested confirmation that every serving node understands the
-/// data-movement per-part checksum sidecar.
-pub const ENV_DATA_MOVEMENT_PART_CHECKSUMS_FLEET_CONFIRMED: &str = "RUSTFS_DATA_MOVEMENT_PART_CHECKSUMS_FLEET_CONFIRMED";
-pub const DEFAULT_DATA_MOVEMENT_PART_CHECKSUMS_FLEET_CONFIRMED: bool = false;
-
-const _: () = assert!(!DEFAULT_DATA_MOVEMENT_PART_CHECKSUMS_WRITE);
-const _: () = assert!(!DEFAULT_DATA_MOVEMENT_PART_CHECKSUMS_FLEET_CONFIRMED);
-
 // =============================================================================
 // Concurrent Request Fix - Timeout and Backpressure Configuration
 // =============================================================================
@@ -680,22 +649,4 @@ mod remote_version_state_tests {
            "RUSTFS_TIER_REMOTE_VERSION_STATE_FLEET_CONFIRMED"
        );
    }
-
-    #[test]
-    fn data_movement_part_checksum_gate_uses_stable_environment_names() {
-        assert_eq!(super::ENV_DATA_MOVEMENT_PART_CHECKSUMS_WRITE, "RUSTFS_DATA_MOVEMENT_PART_CHECKSUMS_WRITE");
-        assert_eq!(
-            super::ENV_DATA_MOVEMENT_PART_CHECKSUMS_FLEET_CONFIRMED,
-            "RUSTFS_DATA_MOVEMENT_PART_CHECKSUMS_FLEET_CONFIRMED"
-        );
-    }
-
-    #[test]
-    fn object_transaction_fencing_gate_uses_stable_environment_names() {
-        assert_eq!(super::ENV_OBJECT_TRANSACTION_FENCING_WRITE, "RUSTFS_OBJECT_TRANSACTION_FENCING_WRITE");
-        assert_eq!(
-            super::ENV_OBJECT_TRANSACTION_FENCING_FLEET_CONFIRMED,
-            "RUSTFS_OBJECT_TRANSACTION_FENCING_FLEET_CONFIRMED"
-        );
-    }
 }
@@ -44,10 +44,6 @@ pub const ENV_OBS_METRICS_EXPORT_ENABLED: &str = "RUSTFS_OBS_METRICS_EXPORT_ENAB
 pub const ENV_OBS_LOGS_EXPORT_ENABLED: &str = "RUSTFS_OBS_LOGS_EXPORT_ENABLED";
 pub const ENV_OBS_PROFILING_EXPORT_ENABLED: &str = "RUSTFS_OBS_PROFILING_EXPORT_ENABLED";

-/// Enables detailed per-stage PUT metrics. Disabled by default because each
-/// PUT records multiple timers and histograms when attribution is active.
-pub const ENV_OBS_PUT_STAGE_METRICS_ENABLED: &str = "RUSTFS_OBS_PUT_STAGE_METRICS_ENABLED";
-
 pub const ENV_OBS_LOGGER_LEVEL: &str = "RUSTFS_OBS_LOGGER_LEVEL";
 pub const ENV_OBS_LOG_STDOUT_ENABLED: &str = "RUSTFS_OBS_LOG_STDOUT_ENABLED";
 pub const ENV_OBS_LOG_DIRECTORY: &str = "RUSTFS_OBS_LOG_DIRECTORY";
@@ -145,7 +141,6 @@ mod tests {
        assert_eq!(ENV_OBS_METRICS_EXPORT_ENABLED, "RUSTFS_OBS_METRICS_EXPORT_ENABLED");
        assert_eq!(ENV_OBS_LOGS_EXPORT_ENABLED, "RUSTFS_OBS_LOGS_EXPORT_ENABLED");
        assert_eq!(ENV_OBS_PROFILING_EXPORT_ENABLED, "RUSTFS_OBS_PROFILING_EXPORT_ENABLED");
-        assert_eq!(ENV_OBS_PUT_STAGE_METRICS_ENABLED, "RUSTFS_OBS_PUT_STAGE_METRICS_ENABLED");
        // Test log cleanup related env keys
        assert_eq!(ENV_OBS_LOG_MAX_TOTAL_SIZE_BYTES, "RUSTFS_OBS_LOG_MAX_TOTAL_SIZE_BYTES");
        assert_eq!(ENV_OBS_LOG_MAX_SINGLE_FILE_SIZE_BYTES, "RUSTFS_OBS_LOG_MAX_SINGLE_FILE_SIZE_BYTES");
@@ -67,10 +67,7 @@ fn configured_capture_log_path(temp_dir: &str) -> Option<String> {
    capture_log_path(Path::new(&log_dir), temp_dir).map(|path| path.to_string_lossy().into_owned())
 }

-pub(crate) fn capture_command_logs(
-    command: &mut Command,
-    log_path: Option<&str>,
-) -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
+fn capture_command_logs(command: &mut Command, log_path: Option<&str>) -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
    let Some(log_path) = log_path else {
        return Ok(());
    };
@@ -2,7 +2,6 @@

 use crate::common::{RustFSTestEnvironment, init_logging, rustfs_binary_path};
 use aws_sdk_s3::primitives::ByteStream;
-use aws_sdk_s3::types::{CompletedMultipartUpload, CompletedPart};
 use serial_test::serial;
 use std::fs;
 use std::path::PathBuf;
@@ -26,15 +25,6 @@ fn generate_compressible_data(size: usize) -> Vec<u8> {
    data
 }

-/// Deterministic 2048-byte-period binary pattern that compresses extremely well: every part
-/// yields many compressed blocks, which is exactly the shape that reproduced the mid-payload
-/// Pending truncation (rustfs/rustfs#5957).
-fn generate_high_ratio_binary_data(size: usize, seed: u8) -> Vec<u8> {
-    (0..size)
-        .map(|i| ((i as u64).wrapping_mul(2_654_435_761).wrapping_add(seed as u64) >> 3) as u8)
-        .collect()
-}
-
 fn find_part_files(temp_dir: &str, bucket: &str, object_key: &str) -> Vec<PathBuf> {
    let bucket_path = PathBuf::from(temp_dir).join(bucket);
    let mut part_files = Vec::new();
@@ -65,14 +55,9 @@ async fn start_rustfs_with_compression(env: &mut RustFSTestEnvironment) -> Resul
    env.cleanup_existing_processes().await?;

    let binary_path = rustfs_binary_path();
-    // Route the child's stdout/stderr through the shared RUSTFS_E2E_LOG_DIR
-    // capture (survives the temp-dir cleanup on Drop and is uploaded as a CI
-    // artifact); without the env var the child inherits stdio as before.
-    let mut command = Command::new(&binary_path);
-    command
+    let process = Command::new(&binary_path)
        .env("RUSTFS_CONSOLE_ENABLE", "false")
        .env("RUSTFS_COMPRESSION_ENABLED", "true")
-        .env("RUSTFS_COMPRESSION_MULTIPART_ENABLED", "true")
        .args([
            "--address",
            &env.address,
@@ -81,9 +66,8 @@ async fn start_rustfs_with_compression(env: &mut RustFSTestEnvironment) -> Resul
            "--secret-key",
            &env.secret_key,
            &env.temp_dir,
-        ]);
-    crate::common::capture_command_logs(&mut command, env.capture_log_path.as_deref())?;
-    let process = command.spawn()?;
+        ])
+        .spawn()?;

    env.process = Some(process);

@@ -170,647 +154,3 @@ async fn test_compression_roundtrip() -> Result<(), Box<dyn std::error::Error +
    env.stop_server();
    Ok(())
 }
-
-const MULTIPART_COMPRESSION_BUCKET: &str = "compression-multipart-bucket";
-const MPU_PART1_SIZE: usize = 5 * 1024 * 1024;
-const MPU_PART2_SIZE: usize = 1024 * 1024;
-
-async fn multipart_upload(
-    client: &aws_sdk_s3::Client,
-    bucket: &str,
-    key: &str,
-    parts: &[&[u8]],
-) -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
-    let create = client.create_multipart_upload().bucket(bucket).key(key).send().await?;
-    let upload_id = create.upload_id().ok_or("missing upload id")?.to_string();
-
-    let mut completed_parts = Vec::with_capacity(parts.len());
-    for (i, part) in parts.iter().enumerate() {
-        let part_number = (i + 1) as i32;
-        let upload = client
-            .upload_part()
-            .bucket(bucket)
-            .key(key)
-            .upload_id(&upload_id)
-            .part_number(part_number)
-            .body(ByteStream::from(part.to_vec()))
-            .send()
-            .await?;
-        completed_parts.push(
-            CompletedPart::builder()
-                .part_number(part_number)
-                .e_tag(upload.e_tag().unwrap_or_default())
-                .build(),
-        );
-    }
-
-    client
-        .complete_multipart_upload()
-        .bucket(bucket)
-        .key(key)
-        .upload_id(&upload_id)
-        .multipart_upload(CompletedMultipartUpload::builder().set_parts(Some(completed_parts)).build())
-        .send()
-        .await?;
-    Ok(())
-}
-
-async fn fetch_range(
-    client: &aws_sdk_s3::Client,
-    bucket: &str,
-    key: &str,
-    range: &str,
-) -> Result<Vec<u8>, Box<dyn std::error::Error + Send + Sync>> {
-    let response = client.get_object().bucket(bucket).key(key).range(range).send().await?;
-    Ok(response.body.collect().await?.into_bytes().to_vec())
-}
-
-/// Multipart disk compression roundtrip: parts are written as independent
-/// compressed streams and every GET shape must reassemble the original bytes
-/// (rustfs/rustfs#5957: multipart uploads previously bypassed disk compression
-/// entirely).
-#[tokio::test]
-#[serial]
-async fn test_compression_multipart_roundtrip() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
-    init_logging();
-    info!("Starting multipart compression roundtrip test");
-
-    let mut env = RustFSTestEnvironment::new().await?;
-    start_rustfs_with_compression(&mut env).await?;
-
-    let client = env.create_s3_client();
-    env.create_test_bucket(MULTIPART_COMPRESSION_BUCKET).await?;
-
-    let object_key = "multipart-compressible.txt";
-    let part1 = generate_compressible_data(MPU_PART1_SIZE);
-    let part2 = generate_compressible_data(MPU_PART2_SIZE);
-    let mut original_data = part1.clone();
-    original_data.extend_from_slice(&part2);
-    let total_size = original_data.len();
-
-    multipart_upload(&client, MULTIPART_COMPRESSION_BUCKET, object_key, &[&part1, &part2]).await?;
-
-    let head_response = client
-        .head_object()
-        .bucket(MULTIPART_COMPRESSION_BUCKET)
-        .key(object_key)
-        .send()
-        .await?;
-    assert_eq!(
-        head_response.content_length().unwrap_or(0) as usize,
-        total_size,
-        "Content-Length should be the logical object size"
-    );
-
-    let part_files = find_part_files(&env.temp_dir, MULTIPART_COMPRESSION_BUCKET, object_key);
-    assert!(!part_files.is_empty(), "expected on-disk part files for the multipart object");
-    let total_physical_size: u64 = part_files.iter().filter_map(|p| fs::metadata(p).ok()).map(|m| m.len()).sum();
-    assert!(
-        total_physical_size < (total_size / 2) as u64,
-        "Physical size {total_physical_size} should be well below original size {total_size} (multipart compression applied)"
-    );
-    info!("Multipart physical storage size: {total_physical_size} bytes (compressed from {total_size} bytes)");
-
-    // Full GET must reassemble both independently compressed parts.
-    let get_response = client
-        .get_object()
-        .bucket(MULTIPART_COMPRESSION_BUCKET)
-        .key(object_key)
-        .send()
-        .await?;
-    let downloaded = get_response.body.collect().await?.into_bytes();
-    assert_eq!(downloaded.len(), total_size);
-    assert_eq!(&downloaded[..], &original_data[..], "full GET data mismatch");
-
-    // Range fully inside part 1.
-    let range_inside_part1 = fetch_range(&client, MULTIPART_COMPRESSION_BUCKET, object_key, "bytes=1024-999423").await?;
-    assert_eq!(&range_inside_part1[..], &original_data[1024..999424], "part-1 range mismatch");
-
-    // Range crossing the part boundary.
-    let boundary_start = MPU_PART1_SIZE - 128 * 1024;
-    let boundary_end = MPU_PART1_SIZE + 128 * 1024 - 1;
-    let range_crossing = fetch_range(
-        &client,
-        MULTIPART_COMPRESSION_BUCKET,
-        object_key,
-        &format!("bytes={boundary_start}-{boundary_end}"),
-    )
-    .await?;
-    assert_eq!(
-        &range_crossing[..],
-        &original_data[boundary_start..boundary_end + 1],
-        "boundary-crossing range mismatch"
-    );
-
-    // Range fully inside part 2.
-    let part2_start = MPU_PART1_SIZE + 4096;
-    let part2_end = MPU_PART1_SIZE + 256 * 1024 - 1;
-    let range_inside_part2 = fetch_range(
-        &client,
-        MULTIPART_COMPRESSION_BUCKET,
-        object_key,
-        &format!("bytes={part2_start}-{part2_end}"),
-    )
-    .await?;
-    assert_eq!(
-        &range_inside_part2[..],
-        &original_data[part2_start..part2_end + 1],
-        "part-2 range mismatch"
-    );
-
-    // Suffix range (last 128 KiB, entirely in part 2).
-    let suffix_len = 128 * 1024;
-    let suffix = fetch_range(&client, MULTIPART_COMPRESSION_BUCKET, object_key, &format!("bytes=-{suffix_len}")).await?;
-    assert_eq!(&suffix[..], &original_data[total_size - suffix_len..], "suffix range mismatch");
-
-    // partNumber GETs must return each original part.
-    for (part_number, expected) in [(1, &part1), (2, &part2)] {
-        let response = client
-            .get_object()
-            .bucket(MULTIPART_COMPRESSION_BUCKET)
-            .key(object_key)
-            .part_number(part_number)
-            .send()
-            .await?;
-        let body = response.body.collect().await?.into_bytes();
-        assert_eq!(&body[..], &expected[..], "partNumber={part_number} GET mismatch");
-    }
-
-    info!("Multipart compression roundtrip test passed");
-    env.delete_test_bucket(MULTIPART_COMPRESSION_BUCKET).await?;
-    env.stop_server();
-    Ok(())
-}
-
-const MPU_HIGH_RATIO_BUCKET: &str = "compression-mpu-high-ratio-bucket";
-
-/// High-ratio binary multipart payload: the object key is on the compression allow-list, so the
-/// disk-compression path runs and each part is stored as many compressed blocks — the shape that
-/// reproduced the mid-payload Pending truncation (rustfs/rustfs#5957). Every GET shape must return
-/// the exact original bytes, and the stored size must show the data really was compressed.
-#[tokio::test]
-#[serial]
-async fn test_compression_multipart_high_ratio_binary_roundtrip() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
-    init_logging();
-    info!("Starting multipart high-ratio binary compression roundtrip test");
-
-    let mut env = RustFSTestEnvironment::new().await?;
-    start_rustfs_with_compression(&mut env).await?;
-
-    let client = env.create_s3_client();
-    env.create_test_bucket(MPU_HIGH_RATIO_BUCKET).await?;
-
-    let object_key = "multipart-high-ratio.txt";
-    let part1 = generate_high_ratio_binary_data(MPU_PART1_SIZE, 7);
-    let part2 = generate_high_ratio_binary_data(MPU_PART2_SIZE, 61);
-    let mut original_data = part1.clone();
-    original_data.extend_from_slice(&part2);
-    let total_size = original_data.len();
-
-    multipart_upload(&client, MPU_HIGH_RATIO_BUCKET, object_key, &[&part1, &part2]).await?;
-
-    let head_response = client
-        .head_object()
-        .bucket(MPU_HIGH_RATIO_BUCKET)
-        .key(object_key)
-        .send()
-        .await?;
-    assert_eq!(
-        head_response.content_length().unwrap_or(0) as usize,
-        total_size,
-        "Content-Length should be the logical object size"
-    );
-
-    // This pattern compresses to roughly 1/50 of its logical size, so a comfortably loose 2x
-    // margin still proves the parts were stored compressed rather than raw or double-encoded.
-    let part_files = find_part_files(&env.temp_dir, MPU_HIGH_RATIO_BUCKET, object_key);
-    assert!(!part_files.is_empty(), "expected on-disk part files for the multipart object");
-    let total_physical_size: u64 = part_files.iter().filter_map(|p| fs::metadata(p).ok()).map(|m| m.len()).sum();
-    assert!(
-        total_physical_size < (total_size as u64) / 2,
-        "Physical size {total_physical_size} should be far below the logical size {total_size} for high-ratio data"
-    );
-    info!("High-ratio multipart physical storage size: {total_physical_size} bytes (logical {total_size} bytes)");
-
-    info!("step: full GET");
-    let get_response = client
-        .get_object()
-        .bucket(MPU_HIGH_RATIO_BUCKET)
-        .key(object_key)
-        .send()
-        .await?;
-    let downloaded = get_response.body.collect().await?.into_bytes();
-    assert_eq!(downloaded.len(), total_size);
-    assert_eq!(&downloaded[..], &original_data[..], "full GET data mismatch");
-
-    // Range crossing the part boundary.
-    info!("step: boundary range GET");
-    let boundary_start = MPU_PART1_SIZE - 128 * 1024;
-    let boundary_end = MPU_PART1_SIZE + 128 * 1024 - 1;
-    let range_crossing = fetch_range(
-        &client,
-        MPU_HIGH_RATIO_BUCKET,
-        object_key,
-        &format!("bytes={boundary_start}-{boundary_end}"),
-    )
-    .await?;
-    assert_eq!(
-        &range_crossing[..],
-        &original_data[boundary_start..boundary_end + 1],
-        "boundary-crossing range mismatch"
-    );
-
-    // partNumber GET for the trailing part.
-    info!("step: partNumber GET");
-    let part2_response = client
-        .get_object()
-        .bucket(MPU_HIGH_RATIO_BUCKET)
-        .key(object_key)
-        .part_number(2)
-        .send()
-        .await?;
-    let part2_body = part2_response.body.collect().await?.into_bytes();
-    assert_eq!(&part2_body[..], &part2[..], "partNumber=2 GET mismatch");
-
-    info!("Multipart high-ratio binary compression roundtrip test passed");
-    env.delete_test_bucket(MPU_HIGH_RATIO_BUCKET).await?;
-    env.stop_server();
-    Ok(())
-}
-
-const MPU_COPY_COMPRESSION_BUCKET: &str = "compression-mpu-copy-bucket";
-const MPU_COPY_SOURCE_SIZE: usize = 6 * 1024 * 1024;
-const MPU_COPY_RANGE_LEN: usize = 5 * 1024 * 1024;
-
-/// UploadPartCopy feeds a part from an already stored (and already compressed) object. The copied
-/// range must be decompressed on read and re-compressed into the destination part, so the final
-/// object has to match "source prefix + uploaded tail" byte for byte.
-#[tokio::test]
-#[serial]
-async fn test_compression_multipart_upload_part_copy_roundtrip() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
-    init_logging();
-    info!("Starting multipart upload-part-copy compression roundtrip test");
-
-    let mut env = RustFSTestEnvironment::new().await?;
-    start_rustfs_with_compression(&mut env).await?;
-
-    let client = env.create_s3_client();
-    env.create_test_bucket(MPU_COPY_COMPRESSION_BUCKET).await?;
-
-    // Source object: a plain PUT that goes through the single-stream compression path.
-    let source_key = "copy-source.txt";
-    let source_data = generate_compressible_data(MPU_COPY_SOURCE_SIZE);
-    client
-        .put_object()
-        .bucket(MPU_COPY_COMPRESSION_BUCKET)
-        .key(source_key)
-        .body(ByteStream::from(source_data.clone()))
-        .send()
-        .await?;
-
-    // Destination object: part 1 copied from the source, part 2 uploaded directly.
-    let target_key = "copy-target.txt";
-    let part2 = generate_compressible_data(MPU_PART2_SIZE);
-    let mut expected_data = source_data[..MPU_COPY_RANGE_LEN].to_vec();
-    expected_data.extend_from_slice(&part2);
-    let total_size = expected_data.len();
-
-    let create = client
-        .create_multipart_upload()
-        .bucket(MPU_COPY_COMPRESSION_BUCKET)
-        .key(target_key)
-        .send()
-        .await?;
-    let upload_id = create.upload_id().ok_or("missing upload id")?.to_string();
-
-    let copy_part = client
-        .upload_part_copy()
-        .bucket(MPU_COPY_COMPRESSION_BUCKET)
-        .key(target_key)
-        .upload_id(&upload_id)
-        .part_number(1)
-        .copy_source(format!("{MPU_COPY_COMPRESSION_BUCKET}/{source_key}"))
-        .copy_source_range(format!("bytes=0-{}", MPU_COPY_RANGE_LEN - 1))
-        .send()
-        .await?;
-    let copy_etag = copy_part
-        .copy_part_result()
-        .and_then(|r| r.e_tag())
-        .ok_or("missing copy part etag")?
-        .to_string();
-
-    let uploaded_part = client
-        .upload_part()
-        .bucket(MPU_COPY_COMPRESSION_BUCKET)
-        .key(target_key)
-        .upload_id(&upload_id)
-        .part_number(2)
-        .body(ByteStream::from(part2.clone()))
-        .send()
-        .await?;
-
-    client
-        .complete_multipart_upload()
-        .bucket(MPU_COPY_COMPRESSION_BUCKET)
-        .key(target_key)
-        .upload_id(&upload_id)
-        .multipart_upload(
-            CompletedMultipartUpload::builder()
-                .parts(CompletedPart::builder().part_number(1).e_tag(copy_etag).build())
-                .parts(
-                    CompletedPart::builder()
-                        .part_number(2)
-                        .e_tag(uploaded_part.e_tag().unwrap_or_default())
-                        .build(),
-                )
-                .build(),
-        )
-        .send()
-        .await?;
-
-    let head_response = client
-        .head_object()
-        .bucket(MPU_COPY_COMPRESSION_BUCKET)
-        .key(target_key)
-        .send()
-        .await?;
-    assert_eq!(
-        head_response.content_length().unwrap_or(0) as usize,
-        total_size,
-        "Content-Length should be the logical object size"
-    );
-
-    let part_files = find_part_files(&env.temp_dir, MPU_COPY_COMPRESSION_BUCKET, target_key);
-    assert!(!part_files.is_empty(), "expected on-disk part files for the copied object");
-    let total_physical_size: u64 = part_files.iter().filter_map(|p| fs::metadata(p).ok()).map(|m| m.len()).sum();
-    assert!(
-        total_physical_size < (total_size / 2) as u64,
-        "Physical size {total_physical_size} should be well below original size {total_size} (copied part compression applied)"
-    );
-
-    let get_response = client
-        .get_object()
-        .bucket(MPU_COPY_COMPRESSION_BUCKET)
-        .key(target_key)
-        .send()
-        .await?;
-    let downloaded = get_response.body.collect().await?.into_bytes();
-    assert_eq!(downloaded.len(), total_size);
-    assert_eq!(&downloaded[..], &expected_data[..], "copied multipart GET data mismatch");
-
-    info!("Multipart upload-part-copy compression roundtrip test passed");
-    env.delete_test_bucket(MPU_COPY_COMPRESSION_BUCKET).await?;
-    env.stop_server();
-    Ok(())
-}
-
-const MPU_THREE_PARTS_BUCKET: &str = "compression-mpu-three-parts-bucket";
-const MPU_THREE_PARTS_TAIL_SIZE: usize = 512 * 1024;
-
-/// Three-part upload with uneven part sizes: each partNumber GET must map back to exactly one
-/// compressed part stream, and a suffix range must resolve inside the trailing part.
-#[tokio::test]
-#[serial]
-async fn test_compression_multipart_three_parts_part_number_gets() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
-    init_logging();
-    info!("Starting three-part multipart compression partNumber test");
-
-    let mut env = RustFSTestEnvironment::new().await?;
-    start_rustfs_with_compression(&mut env).await?;
-
-    let client = env.create_s3_client();
-    env.create_test_bucket(MPU_THREE_PARTS_BUCKET).await?;
-
-    let object_key = "multipart-three-parts.txt";
-    let part1 = generate_compressible_data(MPU_PART1_SIZE);
-    let part2 = generate_compressible_data(MPU_PART1_SIZE);
-    let part3 = generate_compressible_data(MPU_THREE_PARTS_TAIL_SIZE);
-    let mut original_data = part1.clone();
-    original_data.extend_from_slice(&part2);
-    original_data.extend_from_slice(&part3);
-    let total_size = original_data.len();
-
-    multipart_upload(&client, MPU_THREE_PARTS_BUCKET, object_key, &[&part1, &part2, &part3]).await?;
-
-    let head_response = client
-        .head_object()
-        .bucket(MPU_THREE_PARTS_BUCKET)
-        .key(object_key)
-        .send()
-        .await?;
-    assert_eq!(
-        head_response.content_length().unwrap_or(0) as usize,
-        total_size,
-        "Content-Length should be the logical object size"
-    );
-
-    let part_files = find_part_files(&env.temp_dir, MPU_THREE_PARTS_BUCKET, object_key);
-    assert!(!part_files.is_empty(), "expected on-disk part files for the multipart object");
-    let total_physical_size: u64 = part_files.iter().filter_map(|p| fs::metadata(p).ok()).map(|m| m.len()).sum();
-    assert!(
-        total_physical_size < (total_size / 2) as u64,
-        "Physical size {total_physical_size} should be well below original size {total_size} (multipart compression applied)"
-    );
-
-    // Every partNumber GET must return exactly the bytes of the corresponding uploaded part.
-    for (part_number, expected) in [(1, &part1), (2, &part2), (3, &part3)] {
-        let response = client
-            .get_object()
-            .bucket(MPU_THREE_PARTS_BUCKET)
-            .key(object_key)
-            .part_number(part_number)
-            .send()
-            .await?;
-        let body = response.body.collect().await?.into_bytes();
-        assert_eq!(&body[..], &expected[..], "partNumber={part_number} GET mismatch");
-    }
-
-    // Suffix range (last 64 KiB) resolves inside the trailing part.
-    let suffix_len = 64 * 1024;
-    let suffix = fetch_range(&client, MPU_THREE_PARTS_BUCKET, object_key, &format!("bytes=-{suffix_len}")).await?;
-    assert_eq!(&suffix[..], &original_data[total_size - suffix_len..], "suffix range mismatch");
-
-    info!("Three-part multipart compression partNumber test passed");
-    env.delete_test_bucket(MPU_THREE_PARTS_BUCKET).await?;
-    env.stop_server();
-    Ok(())
-}
-
-const MPU_SSE_COMPRESSION_BUCKET: &str = "compression-mpu-sse-bucket";
-
-async fn start_rustfs_with_compression_and_sse(
-    env: &mut RustFSTestEnvironment,
-) -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
-    use base64::Engine;
-    env.cleanup_existing_processes().await?;
-
-    let binary_path = rustfs_binary_path();
-    let master_key = base64::engine::general_purpose::STANDARD.encode([0x42u8; 32]);
-    // Server output goes to a file inside the per-test temp dir so a failing
-    // run can be diagnosed from the child's logs.
-    let server_log = std::fs::File::create(format!("{}/server.log", env.temp_dir))?;
-    let server_log_err = server_log.try_clone()?;
-    let process = Command::new(&binary_path)
-        .env("RUSTFS_CONSOLE_ENABLE", "false")
-        .env("RUSTFS_COMPRESSION_ENABLED", "true")
-        .env("RUSTFS_COMPRESSION_MULTIPART_ENABLED", "true")
-        .env("RUSTFS_SSE_S3_MASTER_KEY", master_key)
-        .env("RUST_LOG", "rustfs=info,rustfs_ecstore=info")
-        .stdout(std::process::Stdio::from(server_log))
-        .stderr(std::process::Stdio::from(server_log_err))
-        .args([
-            "--address",
-            &env.address,
-            "--access-key",
-            &env.access_key,
-            "--secret-key",
-            &env.secret_key,
-            &env.temp_dir,
-        ])
-        .spawn()?;
-
-    env.process = Some(process);
-
-    info!("Waiting for RustFS server with compression + SSE-S3 enabled on {}", env.address);
-    for i in 0..30 {
-        if TcpStream::connect(&env.address).await.is_ok() {
-            info!("RustFS server is ready after {} attempts", i + 1);
-            return Ok(());
-        }
-        if i == 29 {
-            return Err("RustFS server failed to become ready".into());
-        }
-        sleep(Duration::from_secs(1)).await;
-    }
-    Ok(())
-}
-
-/// SSE-S3 + disk compression multipart: each part is compressed and then encrypted, and every GET
-/// shape must still return the original plaintext bytes. Physical size must shrink because the
-/// compression runs before encryption.
-#[tokio::test]
-#[serial]
-async fn test_compression_multipart_sse_s3_roundtrip() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
-    use aws_sdk_s3::types::ServerSideEncryption;
-
-    init_logging();
-    info!("Starting SSE-S3 multipart compression roundtrip test");
-
-    let mut env = RustFSTestEnvironment::new().await?;
-    start_rustfs_with_compression_and_sse(&mut env).await?;
-
-    let client = env.create_s3_client();
-    env.create_test_bucket(MPU_SSE_COMPRESSION_BUCKET).await?;
-
-    let object_key = "multipart-sse-compressible.txt";
-    let part1 = generate_compressible_data(MPU_PART1_SIZE);
-    let part2 = generate_compressible_data(MPU_PART2_SIZE);
-    let mut original_data = part1.clone();
-    original_data.extend_from_slice(&part2);
-    let total_size = original_data.len();
-
-    let create = client
-        .create_multipart_upload()
-        .bucket(MPU_SSE_COMPRESSION_BUCKET)
-        .key(object_key)
-        .server_side_encryption(ServerSideEncryption::Aes256)
-        .send()
-        .await?;
-    let upload_id = create.upload_id().ok_or("missing upload id")?.to_string();
-
-    let mut completed_parts = Vec::new();
-    for (i, part) in [&part1, &part2].into_iter().enumerate() {
-        let part_number = (i + 1) as i32;
-        let upload = client
-            .upload_part()
-            .bucket(MPU_SSE_COMPRESSION_BUCKET)
-            .key(object_key)
-            .upload_id(&upload_id)
-            .part_number(part_number)
-            .body(ByteStream::from(part.clone()))
-            .send()
-            .await?;
-        completed_parts.push(
-            CompletedPart::builder()
-                .part_number(part_number)
-                .e_tag(upload.e_tag().unwrap_or_default())
-                .build(),
-        );
-    }
-
-    client
-        .complete_multipart_upload()
-        .bucket(MPU_SSE_COMPRESSION_BUCKET)
-        .key(object_key)
-        .upload_id(&upload_id)
-        .multipart_upload(CompletedMultipartUpload::builder().set_parts(Some(completed_parts)).build())
-        .send()
-        .await?;
-
-    let head_response = client
-        .head_object()
-        .bucket(MPU_SSE_COMPRESSION_BUCKET)
-        .key(object_key)
-        .send()
-        .await?;
-    assert_eq!(
-        head_response.content_length().unwrap_or(0) as usize,
-        total_size,
-        "Content-Length should be the logical object size"
-    );
-    assert_eq!(
-        head_response.server_side_encryption(),
-        Some(&ServerSideEncryption::Aes256),
-        "HEAD must report SSE-S3"
-    );
-
-    let part_files = find_part_files(&env.temp_dir, MPU_SSE_COMPRESSION_BUCKET, object_key);
-    assert!(!part_files.is_empty(), "expected on-disk part files for the multipart object");
-    let total_physical_size: u64 = part_files.iter().filter_map(|p| fs::metadata(p).ok()).map(|m| m.len()).sum();
-    assert!(
-        total_physical_size < (total_size / 2) as u64,
-        "Physical size {total_physical_size} should be well below original size {total_size} (compress-then-encrypt applied)"
-    );
-
-    let get_response = client
-        .get_object()
-        .bucket(MPU_SSE_COMPRESSION_BUCKET)
-        .key(object_key)
-        .send()
-        .await?;
-    let downloaded = get_response.body.collect().await?.into_bytes();
-    assert_eq!(downloaded.len(), total_size);
-    assert_eq!(&downloaded[..], &original_data[..], "SSE-S3 multipart full GET data mismatch");
-
-    // Range crossing the part boundary must decrypt and decompress across parts.
-    let boundary_start = MPU_PART1_SIZE - 64 * 1024;
-    let boundary_end = MPU_PART1_SIZE + 64 * 1024 - 1;
-    let range_crossing = fetch_range(
-        &client,
-        MPU_SSE_COMPRESSION_BUCKET,
-        object_key,
-        &format!("bytes={boundary_start}-{boundary_end}"),
-    )
-    .await?;
-    assert_eq!(
-        &range_crossing[..],
-        &original_data[boundary_start..boundary_end + 1],
-        "SSE-S3 boundary-crossing range mismatch"
-    );
-
-    // partNumber GET for the trailing part.
-    let part2_response = client
-        .get_object()
-        .bucket(MPU_SSE_COMPRESSION_BUCKET)
-        .key(object_key)
-        .part_number(2)
-        .send()
-        .await?;
-    let part2_body = part2_response.body.collect().await?.into_bytes();
-    assert_eq!(&part2_body[..], &part2[..], "SSE-S3 partNumber=2 GET mismatch");
-
-    info!("SSE-S3 multipart compression roundtrip test passed");
-    env.delete_test_bucket(MPU_SSE_COMPRESSION_BUCKET).await?;
-    env.stop_server();
-    Ok(())
-}
@@ -1828,36 +1828,33 @@ async fn four_node_compressed_inline_fallback() -> TestResult {
    Ok(())
 }

-/// Multipart disk compression is live again, so a compression-enabled cluster classifies multipart objects as compressed and the roundtrip (full GET plus partNumber GET) must still return the original bytes.
-/// Reverting the multipart compression fix must fail this test.
 #[tokio::test]
 #[serial]
-async fn four_node_multipart_disk_compression_roundtrip() -> TestResult {
+async fn four_node_multipart_ignores_disk_compression_fallback() -> TestResult {
    init_logging();

    let collector = OtlpMetricCollector::start().await?;
    let mut cluster = RustFSTestClusterEnvironment::new(4).await?;
    configure_reader_metric_cluster(&mut cluster, &collector);
    cluster.set_env("RUSTFS_COMPRESSION_ENABLED", "true");
-    cluster.set_env("RUSTFS_COMPRESSION_MULTIPART_ENABLED", "true");
    cluster.start().await?;

-    let bucket = "inline-multipart-compression-roundtrip";
+    let bucket = "inline-multipart-compression-fallback";
    cluster.create_test_bucket(bucket).await?;
    let client = cluster.create_s3_client(0)?;
-    let key = "multipart/compressed.txt";
+    let key = "multipart/compression-disabled.txt";
    let (body, second_part, etag) = put_two_part_multipart(&client, bucket, key).await?;

    assert_reader_path(
        &collector,
        &client,
-        ReaderPathExpectation::for_class(ReaderObject::new(bucket, key, &body, etag.as_deref(), None), LEGACY_DUPLEX, COMPRESSED),
+        ReaderPathExpectation::for_class(ReaderObject::new(bucket, key, &body, etag.as_deref(), None), LEGACY_DUPLEX, MULTIPART),
    )
    .await?;
    assert_part_number_reader_path(
        &collector,
        &client,
-        PartNumberReaderPathExpectation::new(bucket, key, &second_part, body.len(), COMPRESSED, LEGACY_DUPLEX),
+        PartNumberReaderPathExpectation::new(bucket, key, &second_part, body.len(), MULTIPART, LEGACY_DUPLEX),
    )
    .await?;

@@ -1874,7 +1871,6 @@ async fn four_node_mixed_msgpack_compat_mode_preserves_fallback_controls() -> Te
    let sse_master_key = base64::engine::general_purpose::STANDARD.encode([0x42u8; 32]);
    cluster.set_env("RUSTFS_SSE_S3_MASTER_KEY", sse_master_key);
    cluster.set_env("RUSTFS_COMPRESSION_ENABLED", "true");
-    cluster.set_env("RUSTFS_COMPRESSION_MULTIPART_ENABLED", "true");
    configure_mixed_msgpack_cluster(&mut cluster, &collector)?;
    cluster.start().await?;

@@ -1894,21 +1890,14 @@ async fn four_node_mixed_msgpack_compat_mode_preserves_fallback_controls() -> Te
        ReaderPathExpectation::for_class(
            ReaderObject::new(bucket, multipart_key, &multipart_body, multipart_etag.as_deref(), None),
            LEGACY_DUPLEX,
-            COMPRESSED,
+            MULTIPART,
        ),
    )
    .await?;
    assert_part_number_reader_path(
        &collector,
        &client,
-        PartNumberReaderPathExpectation::new(
-            bucket,
-            multipart_key,
-            &second_part,
-            multipart_body.len(),
-            COMPRESSED,
-            LEGACY_DUPLEX,
-        ),
+        PartNumberReaderPathExpectation::new(bucket, multipart_key, &second_part, multipart_body.len(), MULTIPART, LEGACY_DUPLEX),
    )
    .await?;
    assert_msgpack_decode_observed(&collector, &decode_before).await?;
@@ -2364,11 +2353,7 @@ async fn four_node_mixed_msgpack_compat_mode_preserves_fallback_controls_during_
    hot_client.create_bucket().bucket(bucket).send().await?;
    put_lifecycle_with_transition_retry(&hot_client, bucket, &tier_name).await?;

-    // `.zip` sits on the disk-compression exclusion list: this test pins
-    // msgpack compat controls across ILM transition, and a compressed object
-    // would classify as `compressed` instead of `remote` (and the warm-tier
-    // read path does not decode compression — tracked separately).
-    let key = "transition/mixed-multipart.zip";
+    let key = "transition/mixed-multipart.bin";
    let (body, second_part, etag) = put_two_part_multipart(&hot_client, bucket, key).await?;
    wait_for_transition(&hot_client, bucket, key, &tier_name).await?;
    assert!(
@@ -97,7 +97,7 @@ async fn start_enforcing_ilm_server(env: &mut LocalKMSTestEnvironment) -> TestRe

    let envs = [
        ("RUSTFS_KMS_ALLOW_INSECURE_DEV_DEFAULTS", "true"),
-        ("RUSTFS_KMS_ENFORCE_SSE_KEY_POLICY", "true"),
+        ("RUSTFS_KMS_ENFORCE_SSE_KEY_POLICY", "false"),
        ("RUSTFS_SCANNER_CYCLE", "1"),
        ("RUSTFS_ILM_PROCESS_TIME", "1"),
        ("RUSTFS_ILM_DEBUG_DAY_SECS", "2"),
@@ -486,6 +486,7 @@ async fn ilm_expiration_on_sse_kms_bucket_under_enforcement() -> TestResult {
 /// depend on scanner scheduling; the 1s scanner cycle stays on as a backstop.
 #[tokio::test]
 #[serial]
+#[ignore = "pins rustfs/rustfs#6025: GET on a transitioned managed-SSE object silently returns corrupt bytes (fails with enforcement on AND off, so it is not an authorization regression); un-ignore with the fix"]
 async fn ilm_transition_on_sse_kms_bucket_under_enforcement_reads_back() -> TestResult {
    init_logging();

@@ -131,8 +131,6 @@ pub mod bucket {
    }

    pub mod metadata_sys {
-        #[cfg(feature = "test-util")]
-        pub use crate::bucket::metadata_sys::ConfigWriteLockProbe;
        pub use crate::bucket::metadata_sys::{
            BucketMetadataMutationGuard, BucketMetadataSys, ObjectLockConfigState, acquire_bucket_metadata_transaction_lock,
            capture_bucket_metadata_incarnation, delete, delete_if_incarnation, get, get_accelerate_config, get_bucket_policy,
@@ -142,7 +140,7 @@ pub mod bucket {
            get_replication_config, get_request_payment_config, get_sse_config, get_tagging_config, get_versioning_config,
            get_website_config, init_bucket_metadata_sys, list_bucket_targets, reload_bucket_metadata, remove_bucket_metadata,
            set_bucket_metadata, update, update_bucket_targets_under_transaction_lock, update_config_with, update_if_incarnation,
-            update_quota_if_incarnation, update_under_transaction_lock,
+            update_under_transaction_lock,
        };
    }

@@ -278,9 +276,7 @@ pub mod cluster {
 }

 pub mod compression {
-    pub use crate::io_support::compress::{
-        MIN_DISK_COMPRESSIBLE_SIZE, is_disk_compressible, is_disk_compression_enabled, is_multipart_disk_compression_enabled,
-    };
+    pub use crate::io_support::compress::{MIN_DISK_COMPRESSIBLE_SIZE, is_disk_compressible, is_disk_compression_enabled};
 }

 pub mod config {
@@ -320,7 +316,7 @@ pub mod data_usage {
        DATA_USAGE_CACHE_NAME, apply_bucket_usage_memory_overlay, compute_bucket_usage,
        init_compression_total_memory_from_backend, invalidate_admin_data_usage_snapshot_cache,
        invalidate_data_usage_snapshot_cache, live_bucket_usage_computations, load_admin_data_usage_from_backend_cached,
-        load_compression_total_from_memory, load_data_usage_from_backend, load_data_usage_from_backend_cached, quota_object_size,
+        load_compression_total_from_memory, load_data_usage_from_backend, load_data_usage_from_backend_cached,
        record_bucket_delete_marker_memory, record_bucket_object_delete_memory, record_bucket_object_version_write_memory,
        record_bucket_object_write_memory, record_bucket_object_write_unknown_previous_memory, record_compression_total_memory,
        refresh_bucket_usage_from_object_layer, refresh_versioned_bucket_usage_from_object_layer,
@@ -407,11 +403,8 @@ pub mod metrics {
 }

 pub mod notification {
-    #[cfg(any(test, feature = "test-util"))]
-    pub use crate::services::notification_sys::rotate_cross_pool_fence_fleet_proof_for_test;
    pub use crate::services::notification_sys::{
-        CrossPoolFenceFleetProofToken, NotificationPeerErr, NotificationSys, acquire_cross_pool_fence_fleet_proof,
-        cross_pool_fence_fleet_proof_matches, get_global_notification_sys, new_global_notification_sys,
+        NotificationPeerErr, NotificationSys, get_global_notification_sys, new_global_notification_sys,
        start_remote_version_state_fleet_probe,
    };
 }
@@ -471,8 +464,7 @@ pub mod set_disk {

    #[cfg(feature = "test-util")]
    pub mod test_util {
-        pub use crate::bucket::quota::reservation::fail_next_quota_ledger_save_for_test;
-        pub use crate::set_disk::{MultipartCommitBarrier, MultipartCommitPause, PutObjectCommitBarrier, PutObjectCommitPause};
+        pub use crate::set_disk::{PutObjectCommitBarrier, PutObjectCommitPause};
    }
 }

@@ -46,13 +46,15 @@ use crate::bucket::lifecycle::transition_transaction::run_transition_transaction
 use crate::bucket::object_lock::ObjectLockApi;
 use crate::bucket::versioning::VersioningApi as _;
 use crate::bucket::versioning_sys::BucketVersioningSys;
+use crate::client::object_api_utils::new_getobjectreader;
 use crate::disk::error::DiskError;
 use crate::disk::{DeleteOptions, Disk, DiskAPI, RUSTFS_META_BUCKET, RUSTFS_META_MULTIPART_BUCKET, STORAGE_FORMAT_FILE};
 use crate::error::Error;
 use crate::error::StorageError;
-use crate::error::{is_err_object_not_found, is_err_read_quorum, is_err_version_not_found, is_network_or_host_down};
+use crate::error::{
+    error_resp_to_object_err, is_err_object_not_found, is_err_read_quorum, is_err_version_not_found, is_network_or_host_down,
+};
 use crate::object_api::{GetObjectReader, ObjectInfo, ObjectOptions};
-use crate::object_api::{ObjectEncryptionResolver, ReadPlan};
 use crate::services::tier::{
    tier::{TierConfigMgr, TierOperationLease, tier_destination_id_from_metadata},
    warm_backend::WarmBackendGetOpts,
@@ -2869,32 +2871,11 @@ fn stale_upload_default_due(initiated: OffsetDateTime, default_expiry: StdDurati
 }

 async fn stale_upload_current_size(set: &Arc<SetDisks>, metadata: &HashMap<String, String>, upload_dir: &str) -> Option<usize> {
-    stale_upload_current_size_with_opts(set, metadata, upload_dir, false).await
-}
-
-async fn stale_upload_current_size_with_opts(
-    set: &Arc<SetDisks>,
-    metadata: &HashMap<String, String>,
-    upload_dir: &str,
-    no_lock: bool,
-) -> Option<usize> {
    let bucket = metadata.get(RUSTFS_MULTIPART_BUCKET_KEY)?;
    let object = metadata.get(RUSTFS_MULTIPART_OBJECT_KEY)?;
    let upload_id = encode_stale_upload_id(upload_dir);
-    let data_movement = rustfs_utils::http::contains_key_str(metadata, rustfs_utils::http::SUFFIX_DATA_MOVEMENT_UPLOAD);
    let parts = set
-        .list_object_parts(
-            bucket,
-            object,
-            &upload_id,
-            None,
-            MAX_PARTS_COUNT,
-            &ObjectOptions {
-                data_movement,
-                no_lock,
-                ..Default::default()
-            },
-        )
+        .list_object_parts(bucket, object, &upload_id, None, MAX_PARTS_COUNT, &ObjectOptions::default())
        .await
        .ok()?;

@@ -2912,12 +2893,7 @@ async fn stale_upload_lifecycle_due(
    metadata: &HashMap<String, String>,
    initiated: OffsetDateTime,
    upload_dir: &str,
-    no_lock: bool,
 ) -> Option<OffsetDateTime> {
-    if rustfs_utils::http::contains_key_str(metadata, rustfs_utils::http::SUFFIX_DATA_MOVEMENT_UPLOAD) {
-        return None;
-    }
-
    let bucket = metadata.get(RUSTFS_MULTIPART_BUCKET_KEY)?;
    let object = metadata.get(RUSTFS_MULTIPART_OBJECT_KEY)?;

@@ -2930,9 +2906,7 @@ async fn stale_upload_lifecycle_due(
        name: object.clone(),
        user_tags: metadata.get(AMZ_OBJECT_TAGGING).cloned().unwrap_or_default(),
        mod_time: Some(initiated),
-        size: stale_upload_current_size_with_opts(set, metadata, upload_dir, no_lock)
-            .await
-            .unwrap_or_default(),
+        size: stale_upload_current_size(set, metadata, upload_dir).await.unwrap_or_default(),
        is_latest: true,
        delete_marker: false,
        user_defined: metadata.clone(),
@@ -2960,7 +2934,6 @@ async fn read_stale_multipart_candidate(
        FileInfoOpts {
            data: false,
            include_free_versions: false,
-            include_part_checksums: false,
        },
    ) {
        Ok(file_info) => (Some(file_info.metadata), file_info.mod_time),
@@ -3000,30 +2973,36 @@ fn merge_stale_multipart_candidate(
    }
 }

-fn is_multipart_sha_dir(path: &str) -> bool {
-    path.len() == 64 && path.bytes().all(|byte| byte.is_ascii_hexdigit())
-}
-
-fn multipart_sha_path(root: &str, entry: &str) -> Option<String> {
-    let sha_dir = entry.trim_end_matches('/');
-    is_multipart_sha_dir(sha_dir).then(|| {
-        if root.is_empty() {
-            sha_dir.to_string()
-        } else {
-            format!("{root}/{sha_dir}")
-        }
-    })
-}
-
 async fn cleanup_empty_multipart_sha_dirs_on_local_disks(set: &Arc<SetDisks>) {
    for disk in set.get_local_disks().await.into_iter().flatten() {
        if !disk.is_online().await {
            continue;
        }

-        for root in ["", crate::set_disk::DATA_MOVEMENT_MULTIPART_PREFIX] {
-            let sha_dirs = match disk
-                .list_dir(RUSTFS_META_MULTIPART_BUCKET, RUSTFS_META_MULTIPART_BUCKET, root, -1)
+        let sha_dirs = match disk
+            .list_dir(RUSTFS_META_MULTIPART_BUCKET, RUSTFS_META_MULTIPART_BUCKET, "", -1)
+            .await
+        {
+            Ok(entries) => entries,
+            Err(err) => {
+                if err != DiskError::FileNotFound && err != DiskError::VolumeNotFound {
+                    debug!(
+                        event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
+                        component = LOG_COMPONENT_ECSTORE,
+                        subsystem = LOG_SUBSYSTEM_LIFECYCLE,
+                        error = ?err,
+                        reason = "multipart_root_list_failed",
+                        "Skipped empty multipart sha cleanup"
+                    );
+                }
+                continue;
+            }
+        };
+
+        for sha_dir in sha_dirs {
+            let sha_dir = sha_dir.trim_end_matches('/').to_string();
+            let upload_dirs = match disk
+                .list_dir(RUSTFS_META_MULTIPART_BUCKET, RUSTFS_META_MULTIPART_BUCKET, &sha_dir, -1)
                .await
            {
                Ok(entries) => entries,
@@ -3033,8 +3012,9 @@ async fn cleanup_empty_multipart_sha_dirs_on_local_disks(set: &Arc<SetDisks>) {
                            event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
                            component = LOG_COMPONENT_ECSTORE,
                            subsystem = LOG_SUBSYSTEM_LIFECYCLE,
+                            sha_dir = %sha_dir,
                            error = ?err,
-                            reason = "multipart_root_list_failed",
+                            reason = "multipart_sha_dir_list_failed",
                            "Skipped empty multipart sha cleanup"
                        );
                    }
@@ -3042,48 +3022,25 @@ async fn cleanup_empty_multipart_sha_dirs_on_local_disks(set: &Arc<SetDisks>) {
                }
            };

-            for sha_dir in sha_dirs.into_iter().filter_map(|entry| multipart_sha_path(root, &entry)) {
-                let upload_dirs = match disk
-                    .list_dir(RUSTFS_META_MULTIPART_BUCKET, RUSTFS_META_MULTIPART_BUCKET, &sha_dir, -1)
-                    .await
-                {
-                    Ok(entries) => entries,
-                    Err(err) => {
-                        if err != DiskError::FileNotFound && err != DiskError::VolumeNotFound {
-                            debug!(
-                                event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
-                                component = LOG_COMPONENT_ECSTORE,
-                                subsystem = LOG_SUBSYSTEM_LIFECYCLE,
-                                sha_dir = %sha_dir,
-                                error = ?err,
-                                reason = "multipart_sha_dir_list_failed",
-                                "Skipped empty multipart sha cleanup"
-                            );
-                        }
-                        continue;
-                    }
-                };
+            if !upload_dirs.is_empty() {
+                continue;
+            }

-                if !upload_dirs.is_empty() {
-                    continue;
-                }
-
-                if let Err(err) = disk
-                    .delete(RUSTFS_META_MULTIPART_BUCKET, &sha_dir, DeleteOptions::default())
-                    .await
-                    && err != DiskError::FileNotFound
-                    && err != DiskError::VolumeNotFound
-                {
-                    debug!(
-                        event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
-                        component = LOG_COMPONENT_ECSTORE,
-                        subsystem = LOG_SUBSYSTEM_LIFECYCLE,
-                        sha_dir = %sha_dir,
-                        error = ?err,
-                        reason = "multipart_sha_dir_remove_failed",
-                        "Failed to remove empty multipart sha dir"
-                    );
-                }
+            if let Err(err) = disk
+                .delete(RUSTFS_META_MULTIPART_BUCKET, &sha_dir, DeleteOptions::default())
+                .await
+                && err != DiskError::FileNotFound
+                && err != DiskError::VolumeNotFound
+            {
+                debug!(
+                    event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
+                    component = LOG_COMPONENT_ECSTORE,
+                    subsystem = LOG_SUBSYSTEM_LIFECYCLE,
+                    sha_dir = %sha_dir,
+                    error = ?err,
+                    reason = "multipart_sha_dir_remove_failed",
+                    "Failed to remove empty multipart sha dir"
+                );
            }
        }
    }
@@ -3101,9 +3058,30 @@ async fn cleanup_stale_multipart_uploads_in_set(set: &Arc<SetDisks>, now: Offset
            continue;
        }

-        for root in ["", crate::set_disk::DATA_MOVEMENT_MULTIPART_PREFIX] {
-            let sha_dirs = match disk
-                .list_dir(RUSTFS_META_MULTIPART_BUCKET, RUSTFS_META_MULTIPART_BUCKET, root, -1)
+        let sha_dirs = match disk
+            .list_dir(RUSTFS_META_MULTIPART_BUCKET, RUSTFS_META_MULTIPART_BUCKET, "", -1)
+            .await
+        {
+            Ok(entries) => entries,
+            Err(err) => {
+                if err != DiskError::FileNotFound && err != DiskError::VolumeNotFound {
+                    debug!(
+                        event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
+                        component = LOG_COMPONENT_ECSTORE,
+                        subsystem = LOG_SUBSYSTEM_LIFECYCLE,
+                        error = ?err,
+                        reason = "multipart_root_list_failed",
+                        "Skipped stale multipart cleanup"
+                    );
+                }
+                continue;
+            }
+        };
+
+        for sha_dir in sha_dirs {
+            let sha_dir = sha_dir.trim_end_matches('/').to_string();
+            let upload_dirs = match disk
+                .list_dir(RUSTFS_META_MULTIPART_BUCKET, RUSTFS_META_MULTIPART_BUCKET, &sha_dir, -1)
                .await
            {
                Ok(entries) => entries,
@@ -3113,8 +3091,9 @@ async fn cleanup_stale_multipart_uploads_in_set(set: &Arc<SetDisks>, now: Offset
                            event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
                            component = LOG_COMPONENT_ECSTORE,
                            subsystem = LOG_SUBSYSTEM_LIFECYCLE,
+                            sha_dir = %sha_dir,
                            error = ?err,
-                            reason = "multipart_root_list_failed",
+                            reason = "multipart_sha_dir_list_failed",
                            "Skipped stale multipart cleanup"
                        );
                    }
@@ -3122,62 +3101,39 @@ async fn cleanup_stale_multipart_uploads_in_set(set: &Arc<SetDisks>, now: Offset
                }
            };

-            for sha_dir in sha_dirs.into_iter().filter_map(|entry| multipart_sha_path(root, &entry)) {
-                let upload_dirs = match disk
-                    .list_dir(RUSTFS_META_MULTIPART_BUCKET, RUSTFS_META_MULTIPART_BUCKET, &sha_dir, -1)
-                    .await
+            for upload_dir in upload_dirs {
+                let upload_dir = upload_dir.trim_end_matches('/').to_string();
+                let candidate_path = format!("{sha_dir}/{upload_dir}");
+                if candidates
+                    .get(&candidate_path)
+                    .is_some_and(|existing: &StaleMultipartUploadCandidate| existing.metadata.is_some())
                {
-                    Ok(entries) => entries,
+                    continue;
+                }
+
+                let candidate = match read_stale_multipart_candidate(disk.as_ref(), &sha_dir, &upload_dir).await {
+                    Ok(candidate) => candidate,
                    Err(err) => {
-                        if err != DiskError::FileNotFound && err != DiskError::VolumeNotFound {
+                        if err != DiskError::FileNotFound {
                            debug!(
                                event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
                                component = LOG_COMPONENT_ECSTORE,
                                subsystem = LOG_SUBSYSTEM_LIFECYCLE,
-                                sha_dir = %sha_dir,
+                                path = %candidate_path,
                                error = ?err,
-                                reason = "multipart_sha_dir_list_failed",
-                                "Skipped stale multipart cleanup"
+                                reason = "multipart_metadata_read_failed",
+                                "Multipart metadata unavailable during stale cleanup"
                            );
                        }
-                        continue;
+                        let initiated = initiated_from_upload_dir(&upload_dir, None);
+                        StaleMultipartUploadCandidate {
+                            path: candidate_path,
+                            initiated,
+                            metadata: None,
+                        }
                    }
                };
-
-                for upload_dir in upload_dirs {
-                    let upload_dir = upload_dir.trim_end_matches('/').to_string();
-                    let candidate_path = format!("{sha_dir}/{upload_dir}");
-                    if candidates
-                        .get(&candidate_path)
-                        .is_some_and(|existing: &StaleMultipartUploadCandidate| existing.metadata.is_some())
-                    {
-                        continue;
-                    }
-
-                    let candidate = match read_stale_multipart_candidate(disk.as_ref(), &sha_dir, &upload_dir).await {
-                        Ok(candidate) => candidate,
-                        Err(err) => {
-                            if err != DiskError::FileNotFound {
-                                debug!(
-                                    event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
-                                    component = LOG_COMPONENT_ECSTORE,
-                                    subsystem = LOG_SUBSYSTEM_LIFECYCLE,
-                                    path = %candidate_path,
-                                    error = ?err,
-                                    reason = "multipart_metadata_read_failed",
-                                    "Multipart metadata unavailable during stale cleanup"
-                                );
-                            }
-                            let initiated = initiated_from_upload_dir(&upload_dir, None);
-                            StaleMultipartUploadCandidate {
-                                path: candidate_path,
-                                initiated,
-                                metadata: None,
-                            }
-                        }
-                    };
-                    merge_stale_multipart_candidate(&mut candidates, candidate);
-                }
+                merge_stale_multipart_candidate(&mut candidates, candidate);
            }
        }
    }
@@ -3186,7 +3142,7 @@ async fn cleanup_stale_multipart_uploads_in_set(set: &Arc<SetDisks>, now: Offset
        let upload_dir = candidate.path.rsplit('/').next().unwrap_or_default().to_string();
        let mut due = stale_upload_default_due(candidate.initiated, default_expiry);
        if let Some(metadata) = candidate.metadata.as_ref()
-            && let Some(lifecycle_due) = stale_upload_lifecycle_due(set, metadata, candidate.initiated, &upload_dir, false).await
+            && let Some(lifecycle_due) = stale_upload_lifecycle_due(set, metadata, candidate.initiated, &upload_dir).await
            && lifecycle_due < due
        {
            due = lifecycle_due;
@@ -3196,49 +3152,34 @@ async fn cleanup_stale_multipart_uploads_in_set(set: &Arc<SetDisks>, now: Offset
            continue;
        }

-        let cleanup_guard = match set.lock_stale_multipart_cleanup(&candidate.path).await {
-            Ok(guard) => guard,
-            Err(err) => {
-                debug!(
-                    event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
-                    component = LOG_COMPONENT_ECSTORE,
-                    subsystem = LOG_SUBSYSTEM_LIFECYCLE,
-                    path = %candidate.path,
-                    error = ?err,
-                    reason = "multipart_cleanup_lock_or_recheck_failed",
-                    "Skipped stale multipart cleanup"
-                );
-                continue;
-            }
-        };
-        let current_metadata = cleanup_guard.file_info().metadata.clone();
-        let current_initiated = initiated_from_upload_dir(&upload_dir, cleanup_guard.file_info().mod_time);
-        let mut current_due = stale_upload_default_due(current_initiated, default_expiry);
-        if let Some(lifecycle_due) =
-            stale_upload_lifecycle_due(set, &current_metadata, current_initiated, &upload_dir, true).await
-            && lifecycle_due < current_due
-        {
-            current_due = lifecycle_due;
-        }
-        if now < current_due || cleanup_guard.is_lock_lost() {
-            continue;
-        }
-
-        match cleanup_guard.delete(set).await {
+        match set.delete_all(RUSTFS_META_MULTIPART_BUCKET, &candidate.path).await {
            Ok(()) => {
                deleted += 1;
                let upload_id = encode_stale_upload_id(&upload_dir);
-                debug!(
-                    bucket = current_metadata.get(RUSTFS_MULTIPART_BUCKET_KEY).cloned().unwrap_or_default(),
-                    object = current_metadata.get(RUSTFS_MULTIPART_OBJECT_KEY).cloned().unwrap_or_default(),
-                    upload_id = %upload_id,
-                    due = ?current_due,
-                    event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
-                    component = LOG_COMPONENT_ECSTORE,
-                    subsystem = LOG_SUBSYSTEM_LIFECYCLE,
-                    state = "removed",
-                    "Removed stale multipart upload"
-                );
+                if let Some(metadata) = candidate.metadata.as_ref() {
+                    debug!(
+                        bucket = metadata.get(RUSTFS_MULTIPART_BUCKET_KEY).cloned().unwrap_or_default(),
+                        object = metadata.get(RUSTFS_MULTIPART_OBJECT_KEY).cloned().unwrap_or_default(),
+                        upload_id = %upload_id,
+                        due = ?due,
+                        event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
+                        component = LOG_COMPONENT_ECSTORE,
+                        subsystem = LOG_SUBSYSTEM_LIFECYCLE,
+                        state = "removed",
+                        "Removed stale multipart upload"
+                    );
+                } else {
+                    debug!(
+                        path = %candidate.path,
+                        upload_id = %upload_id,
+                        due = ?due,
+                        event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
+                        component = LOG_COMPONENT_ECSTORE,
+                        subsystem = LOG_SUBSYSTEM_LIFECYCLE,
+                        state = "removed",
+                        "Removed stale multipart upload"
+                    );
+                }
            }
            Err(err) => debug!(
                event = EVENT_LIFECYCLE_STALE_MULTIPART_CLEANUP,
@@ -4398,10 +4339,9 @@ pub async fn get_transitioned_object_reader(
    h: &HeaderMap,
    oi: &ObjectInfo,
    opts: &ObjectOptions,
-    resolver: Option<&dyn ObjectEncryptionResolver>,
 ) -> Result<GetObjectReader, std::io::Error> {
    let tier_config_mgr = runtime_sources::tier_config_mgr_handle();
-    get_transitioned_object_reader_with_tier_manager(bucket, object, rs, h, oi, opts, &tier_config_mgr, resolver).await
+    get_transitioned_object_reader_with_tier_manager(bucket, object, rs, h, oi, opts, &tier_config_mgr).await
 }

 fn validate_transition_remote_version(oi: &ObjectInfo) -> Result<bool, std::io::Error> {
@@ -4421,10 +4361,6 @@ fn validate_transition_remote_version(oi: &ObjectInfo) -> Result<bool, std::io::
    }
 }

-// The resolver joins the tier manager as the second injected port this read
-// needs; grouping the request half into a struct would churn every call site of
-// a bug fix.
-#[allow(clippy::too_many_arguments)]
 pub(crate) async fn get_transitioned_object_reader_with_tier_manager(
    bucket: &str,
    object: &str,
@@ -4433,7 +4369,6 @@ pub(crate) async fn get_transitioned_object_reader_with_tier_manager(
    oi: &ObjectInfo,
    opts: &ObjectOptions,
    tier_config_mgr: &Arc<RwLock<TierConfigMgr>>,
-    resolver: Option<&dyn ObjectEncryptionResolver>,
 ) -> Result<GetObjectReader, std::io::Error> {
    validate_transition_remote_version(oi)?;
    let expected_identity = tier_destination_id_from_metadata(&oi.user_defined)?;
@@ -4451,16 +4386,11 @@ pub(crate) async fn get_transitioned_object_reader_with_tier_manager(

    tgt_client.validate_remote_version_id(&oi.transitioned_object.version_id)?;

-    // The same read plan the local path uses, so the tier fetch is positioned in
-    // the object's *stored* coordinate system and the stream is handed the same
-    // decrypt/decompress transforms. Reading an encrypted object's ciphertext
-    // through a plaintext-coordinate range and skipping the transform is how a
-    // transitioned SSE object used to come back as silently corrupt bytes of the
-    // right length (rustfs/rustfs#6025).
-    let plan = ReadPlan::build_for_request(rs.clone(), oi, opts, h, resolver)
-        .await
-        .map_err(|err| std::io::Error::other(format!("building the read plan for {bucket}/{object} failed: {err}")))?;
-    let (off, length) = (plan.storage_offset() as i64, plan.storage_length());
+    let ret = new_getobjectreader(rs, oi, opts, h);
+    if let Err(err) = ret {
+        return Err(error_resp_to_object_err(err, vec![bucket, object]));
+    }
+    let (get_fn, off, length) = ret.expect("get_transitioned_object_reader should succeed after error check");
    let mut gopts = WarmBackendGetOpts::default();

    if off >= 0 && length >= 0 {
@@ -4497,10 +4427,7 @@ pub(crate) async fn get_transitioned_object_reader_with_tier_manager(
            );
            e
        })?;
-    let object_reader = plan
-        .into_object_reader(Box::new(reader), oi)
-        .map_err(|err| std::io::Error::other(format!("wrapping the tier stream for {bucket}/{object} failed: {err}")))?;
-    Ok(attach_tier_operation_lease(object_reader, tgt_client))
+    Ok(attach_tier_operation_lease(get_fn(reader, h.clone()), tgt_client))
 }

 struct TierOperationLeaseReader {
@@ -5235,7 +5162,6 @@ mod tests {
    use crate::services::tier::tier::TierConfigMgr;
    #[cfg(feature = "test-util")]
    use crate::services::tier::warm_backend::WarmBackend as _;
-    use crate::set_disk::{MultipartCommitBarrier, MultipartCommitPause};
    use crate::set_disk::{RUSTFS_MULTIPART_BUCKET_KEY, RUSTFS_MULTIPART_OBJECT_KEY};
    use crate::storage_api_contracts::namespace::NamespaceLocking as _;
    use crate::storage_api_contracts::{
@@ -5788,7 +5714,6 @@ mod tests {
            &object_info,
            &ObjectOptions::default(),
            &manager,
-            None,
        )
        .await
        .expect("transitioned reader should open");
@@ -5853,7 +5778,6 @@ mod tests {
            &object_info,
            &ObjectOptions::default(),
            &manager,
-            None,
        )
        .await
        {
@@ -5894,7 +5818,6 @@ mod tests {
            &object_info,
            &ObjectOptions::default(),
            &manager,
-            None,
        )
        .await
        {
@@ -6132,7 +6055,6 @@ mod tests {
            &oi,
            &ObjectOptions::default(),
            &manager,
-            None,
        )
        .await
        {
@@ -6156,7 +6078,6 @@ mod tests {
            &oi,
            &ObjectOptions::default(),
            &manager,
-            None,
        )
        .await
        {
@@ -12005,135 +11926,6 @@ mod tests {
        assert!(is_err_invalid_upload_id(&err));
    }

-    #[tokio::test]
-    #[serial]
-    async fn stale_multipart_cleanup_handles_data_movement_namespace() {
-        let (_paths, ecstore) = setup_test_env().await;
-        let bucket = format!("stale-data-movement-{}", Uuid::new_v4().simple());
-        create_test_bucket(&ecstore, &bucket).await;
-
-        let create_upload = |object: &'static str, mod_time| {
-            let ecstore = ecstore.clone();
-            let bucket = bucket.clone();
-            async move {
-                let mut metadata = HashMap::new();
-                rustfs_utils::http::insert_str(
-                    &mut metadata,
-                    rustfs_utils::http::SUFFIX_DATA_MOVEMENT_UPLOAD,
-                    "cleanup-test".to_string(),
-                );
-                ecstore
-                    .new_multipart_upload(
-                        &bucket,
-                        object,
-                        &ObjectOptions {
-                            data_movement: true,
-                            mod_time: Some(mod_time),
-                            user_defined: metadata,
-                            ..Default::default()
-                        },
-                    )
-                    .await
-                    .expect("data movement multipart upload should be created")
-                    .upload_id
-            }
-        };
-
-        let stale_object = "stale-internal.bin";
-        let active_object = "active-internal.bin";
-        let now = OffsetDateTime::now_utc();
-        let stale_upload_id = create_upload(stale_object, now - time::Duration::hours(30)).await;
-        let active_upload_id = create_upload(active_object, now).await;
-
-        let deleted = cleanup_stale_multipart_uploads_once_at(ecstore.clone(), now, StdDuration::from_secs(24 * 60 * 60)).await;
-        assert!(deleted >= 1, "expected stale data movement upload to be removed");
-
-        let internal_opts = ObjectOptions {
-            data_movement: true,
-            ..Default::default()
-        };
-        let stale_err = ecstore
-            .get_multipart_info(&bucket, stale_object, &stale_upload_id, &internal_opts)
-            .await
-            .expect_err("stale data movement upload should be removed");
-        assert!(is_err_invalid_upload_id(&stale_err));
-        ecstore
-            .get_multipart_info(&bucket, active_object, &active_upload_id, &internal_opts)
-            .await
-            .expect("active data movement upload should remain available");
-    }
-
-    #[tokio::test]
-    #[serial]
-    async fn stale_multipart_cleanup_waits_for_data_movement_part_commit() {
-        let (_paths, ecstore) = setup_test_env().await;
-        let bucket = format!("stale-data-movement-lock-{}", Uuid::new_v4().simple());
-        let object = "stale-internal.bin";
-        create_test_bucket(&ecstore, &bucket).await;
-
-        let mut metadata = HashMap::new();
-        rustfs_utils::http::insert_str(
-            &mut metadata,
-            rustfs_utils::http::SUFFIX_DATA_MOVEMENT_UPLOAD,
-            "cleanup-lock-test".to_string(),
-        );
-        let opts = ObjectOptions {
-            data_movement: true,
-            mod_time: Some(OffsetDateTime::now_utc() - time::Duration::hours(30)),
-            user_defined: metadata,
-            ..Default::default()
-        };
-        let upload = ecstore
-            .new_multipart_upload(&bucket, object, &opts)
-            .await
-            .expect("data movement multipart upload should be created");
-        let barrier = MultipartCommitBarrier::install(bucket.as_str(), object, MultipartCommitPause::PutPartAfterRename);
-        let put_store = ecstore.clone();
-        let put_bucket = bucket.clone();
-        let upload_id = upload.upload_id.clone();
-        let put_task = tokio::spawn(async move {
-            let mut data = PutObjReader::from_vec(vec![1, 2, 3, 4]);
-            put_store
-                .put_object_part(
-                    &put_bucket,
-                    object,
-                    &upload_id,
-                    1,
-                    &mut data,
-                    &ObjectOptions {
-                        data_movement: true,
-                        ..Default::default()
-                    },
-                )
-                .await
-        });
-        barrier.wait_until_paused().await;
-
-        let cleanup_store = ecstore.clone();
-        let mut cleanup_task = tokio::spawn(async move {
-            cleanup_stale_multipart_uploads_once_at(
-                cleanup_store,
-                OffsetDateTime::now_utc(),
-                StdDuration::from_secs(24 * 60 * 60),
-            )
-            .await
-        });
-        assert!(
-            tokio::time::timeout(StdDuration::from_millis(200), &mut cleanup_task)
-                .await
-                .is_err(),
-            "stale cleanup must wait for the in-flight part commit upload lock"
-        );
-
-        barrier.release();
-        put_task
-            .await
-            .expect("part upload task should join")
-            .expect("part upload should commit before stale cleanup");
-        let deleted = cleanup_task.await.expect("stale cleanup task should join");
-        assert!(deleted >= 1, "stale cleanup should proceed after the part commit releases its lock");
-    }
-
    #[tokio::test]
    #[serial]
    async fn stale_multipart_cleanup_applies_abort_incomplete_lifecycle_before_default_expiry() {
@@ -12208,58 +12000,6 @@ mod tests {
        assert!(is_err_invalid_upload_id(&err));
    }

-    #[tokio::test]
-    #[serial]
-    async fn stale_multipart_cleanup_excludes_data_movement_from_abort_lifecycle() {
-        let (_paths, ecstore) = setup_test_env().await;
-        let bucket = format!("stale-internal-lifecycle-{}", Uuid::new_v4().simple());
-        let object = "logs/internal/object.bin";
-        create_test_bucket(&ecstore, &bucket).await;
-        set_abort_incomplete_lifecycle(&bucket, "logs/", 0).await;
-
-        let initiated = OffsetDateTime::now_utc() - time::Duration::minutes(5);
-        let mut metadata = HashMap::new();
-        rustfs_utils::http::insert_str(
-            &mut metadata,
-            rustfs_utils::http::SUFFIX_DATA_MOVEMENT_UPLOAD,
-            "lifecycle-exclusion-test".to_string(),
-        );
-        let upload = ecstore
-            .new_multipart_upload(
-                &bucket,
-                object,
-                &ObjectOptions {
-                    data_movement: true,
-                    mod_time: Some(initiated),
-                    user_defined: metadata,
-                    ..Default::default()
-                },
-            )
-            .await
-            .expect("data movement multipart upload should be created");
-
-        let deleted = cleanup_stale_multipart_uploads_once_at(
-            ecstore.clone(),
-            OffsetDateTime::now_utc(),
-            StdDuration::from_secs(7 * 24 * 60 * 60),
-        )
-        .await;
-        assert_eq!(deleted, 0, "bucket lifecycle must not remove active data movement uploads");
-
-        ecstore
-            .get_multipart_info(
-                &bucket,
-                object,
-                &upload.upload_id,
-                &ObjectOptions {
-                    data_movement: true,
-                    ..Default::default()
-                },
-            )
-            .await
-            .expect("active data movement upload should remain available");
-    }
-
    #[tokio::test]
    #[serial]
    async fn stale_multipart_cleanup_applies_abort_lifecycle_with_size_filter() {
@@ -50,72 +50,6 @@ use uuid::Uuid;

 const BUCKET_METADATA_REFRESH_INTERVAL: Duration = Duration::from_secs(15 * 60);

-#[cfg(any(test, feature = "test-util"))]
-struct ConfigWriteLockProbeState {
-    bucket: String,
-    arrived: tokio::sync::Notify,
-}
-
-#[cfg(any(test, feature = "test-util"))]
-static CONFIG_WRITE_LOCK_PROBES: std::sync::OnceLock<StdMutex<Vec<Arc<ConfigWriteLockProbeState>>>> = std::sync::OnceLock::new();
-
-#[cfg(any(test, feature = "test-util"))]
-pub struct ConfigWriteLockProbe {
-    state: Arc<ConfigWriteLockProbeState>,
-}
-
-#[cfg(any(test, feature = "test-util"))]
-impl ConfigWriteLockProbe {
-    pub fn install(bucket: &str) -> Self {
-        let state = Arc::new(ConfigWriteLockProbeState {
-            bucket: bucket.to_string(),
-            arrived: tokio::sync::Notify::new(),
-        });
-        let mut probes = CONFIG_WRITE_LOCK_PROBES
-            .get_or_init(|| StdMutex::new(Vec::new()))
-            .lock()
-            .expect("config write lock probe mutex should not poison");
-        assert!(
-            !probes.iter().any(|current| current.bucket == state.bucket),
-            "config write lock probe must be unique for a bucket"
-        );
-        probes.push(Arc::clone(&state));
-        drop(probes);
-        Self { state }
-    }
-
-    pub async fn wait_until_attempted(&self) {
-        tokio::time::timeout(Duration::from_secs(30), self.state.arrived.notified())
-            .await
-            .expect("bucket config update should attempt the transaction lock");
-    }
-}
-
-#[cfg(any(test, feature = "test-util"))]
-impl Drop for ConfigWriteLockProbe {
-    fn drop(&mut self) {
-        let mut probes = CONFIG_WRITE_LOCK_PROBES
-            .get_or_init(|| StdMutex::new(Vec::new()))
-            .lock()
-            .expect("config write lock probe mutex should not poison");
-        probes.retain(|state| !Arc::ptr_eq(state, &self.state));
-    }
-}
-
-#[cfg(any(test, feature = "test-util"))]
-fn notify_config_write_lock_attempt(bucket: &str) {
-    let probe = CONFIG_WRITE_LOCK_PROBES
-        .get_or_init(|| StdMutex::new(Vec::new()))
-        .lock()
-        .expect("config write lock probe mutex should not poison")
-        .iter()
-        .find(|probe| probe.bucket == bucket)
-        .cloned();
-    if let Some(probe) = probe {
-        probe.arrived.notify_one();
-    }
-}
-
 #[derive(Clone, Copy)]
 enum MetadataLoadMode {
    Initial,
@@ -656,31 +590,6 @@ pub async fn update_under_transaction_lock(
    update_under_config_write_guard(get_bucket_metadata_sys()?, guard, config_file, data).await
 }

-pub async fn update_quota_if_incarnation(
-    bucket: &str,
-    data: Vec<u8>,
-    expected_incarnation_id: Uuid,
-    proof: &crate::services::notification_sys::CrossPoolFenceFleetProofToken,
-) -> Result<OffsetDateTime> {
-    let sys = get_bucket_metadata_sys()?;
-    let guard = Box::pin(acquire_config_write_guard_for_incarnation(
-        sys.clone(),
-        bucket,
-        Some(expected_incarnation_id),
-    ))
-    .await?;
-    if !crate::services::notification_sys::cross_pool_fence_fleet_proof_matches(proof) {
-        return Err(Error::NamespaceLockQuorumUnavailable {
-            mode: "quota_capability",
-            bucket: bucket.to_string(),
-            object: rustfs_config::QUOTA_CONFIG_FILE.to_string(),
-            required: 1,
-            achieved: 0,
-        });
-    }
-    update_under_config_write_guard(sys, &guard, rustfs_config::QUOTA_CONFIG_FILE, data).await
-}
-
 pub async fn update_bucket_targets_under_transaction_lock(
    guard: &BucketMetadataMutationGuard,
    bucket: &str,
@@ -825,26 +734,7 @@ async fn acquire_transaction_lock_with_sys(
    let lock = api
        .new_ns_lock(RUSTFS_META_BUCKET, &bucket_metadata_transaction_lock_key(bucket))
        .await?;
-    let acquire = lock.get_write_lock(crate::set_disk::get_lock_acquire_timeout());
-    #[cfg(any(test, feature = "test-util"))]
-    {
-        tokio::pin!(acquire);
-        let mut notified = false;
-        let guard = futures::future::poll_fn(|cx| match std::future::Future::poll(acquire.as_mut(), cx) {
-            std::task::Poll::Pending => {
-                if !notified {
-                    notify_config_write_lock_attempt(bucket);
-                    notified = true;
-                }
-                std::task::Poll::Pending
-            }
-            std::task::Poll::Ready(result) => std::task::Poll::Ready(result),
-        })
-        .await?;
-        Ok(guard)
-    }
-    #[cfg(not(any(test, feature = "test-util")))]
-    Ok(acquire.await?)
+    Ok(lock.get_write_lock(crate::set_disk::get_lock_acquire_timeout()).await?)
 }

 /// The lock resource name is deliberately still the `bucket-targets` one it
@@ -999,37 +889,6 @@ pub(crate) async fn get_object_lock_config_and_incarnation_from_disk_in(
    }
 }

-/// Re-read the quota configuration and bucket incarnation from the same
-/// authoritative metadata blob while the caller holds the bucket metadata
-/// transaction read lock.
-pub(crate) async fn get_quota_config_and_incarnation_from_disk_in(
-    ctx: &crate::runtime::instance::InstanceContext,
-    bucket: &str,
-) -> Result<(Option<BucketQuota>, Uuid, OffsetDateTime)> {
-    let bucket_meta_sys_lock = bucket_metadata_sys_of(ctx)?;
-    let bucket_meta_sys = bucket_meta_sys_lock.read().await.clone();
-
-    match bucket_meta_sys
-        .read_authoritative_metadata_from_disk_under_transaction_lock(bucket)
-        .await?
-    {
-        BucketMetadataAuthority::Authoritative(metadata)
-            if metadata.bucket_incarnation_sidecar && !metadata.bucket_incarnation_id.is_nil() =>
-        {
-            Ok((
-                metadata.quota_config.clone(),
-                metadata.bucket_incarnation_id,
-                metadata.quota_config_updated_at,
-            ))
-        }
-        BucketMetadataAuthority::Authoritative(_) => {
-            Err(Error::other(format!("bucket incarnation metadata is not authoritative: {bucket}")))
-        }
-        BucketMetadataAuthority::MissingBucket => Err(Error::BucketNotFound(bucket.to_string())),
-        BucketMetadataAuthority::Fabricated => Err(Error::other(format!("bucket quota metadata is not authoritative: {bucket}"))),
-    }
-}
-
 pub async fn get_replication_config(bucket: &str) -> Result<(ReplicationConfiguration, OffsetDateTime)> {
    let bucket_meta_sys_lock = get_bucket_metadata_sys()?;
    let bucket_meta_sys = bucket_meta_sys_lock.read().await;
@@ -52,7 +52,6 @@ impl QuotaChecker {
    ) -> Result<QuotaCheckResult, QuotaError> {
        let start_time = Instant::now();
        let quota_config = self.get_quota_config(bucket).await?;
-        let uses_durable_reservations = quota_config.uses_durable_reservations();

        // If no quota limit is set, allow operation
        let quota_limit = match quota_config.quota {
@@ -68,7 +67,6 @@ impl QuotaChecker {
                    quota_limit: None,
                    operation_size,
                    remaining: None,
-                    uses_durable_reservations,
                });
            }
            Some(q) => q,
@@ -76,17 +74,14 @@ impl QuotaChecker {

        let current_usage = self.get_real_time_usage(bucket).await?;

-        let admission_size = if uses_durable_reservations { 0 } else { operation_size };
        let expected_usage = match operation {
-            QuotaOperation::PutObject | QuotaOperation::PostObject | QuotaOperation::CopyObject => {
-                current_usage.saturating_add(admission_size)
-            }
+            QuotaOperation::PutObject | QuotaOperation::PostObject | QuotaOperation::CopyObject => current_usage + operation_size,
            QuotaOperation::DeleteObject => current_usage.saturating_sub(operation_size),
        };

        let allowed = match operation {
            QuotaOperation::PutObject | QuotaOperation::PostObject | QuotaOperation::CopyObject => {
-                quota_config.check_operation_allowed(current_usage, admission_size)
+                quota_config.check_operation_allowed(current_usage, operation_size)
            }
            QuotaOperation::DeleteObject => true,
        };
@@ -110,7 +105,6 @@ impl QuotaChecker {
            quota_limit: Some(quota_limit),
            operation_size,
            remaining,
-            uses_durable_reservations,
        };

        let duration = start_time.elapsed();
@@ -164,26 +158,6 @@ impl QuotaChecker {
            .await
    }

-    pub async fn set_durable_quota_config_if_incarnation(
-        &mut self,
-        bucket: &str,
-        quota: BucketQuota,
-        expected_incarnation_id: uuid::Uuid,
-        proof: &crate::services::notification_sys::CrossPoolFenceFleetProofToken,
-    ) -> Result<OffsetDateTime, QuotaError> {
-        let json_data = serde_json::to_vec(&quota).map_err(|e| QuotaError::InvalidConfig {
-            reason: format!("Failed to serialize quota config: {}", e),
-        })?;
-        let start_time = Instant::now();
-        let updated_at =
-            crate::bucket::metadata_sys::update_quota_if_incarnation(bucket, json_data, expected_incarnation_id, proof)
-                .await
-                .map_err(QuotaError::StorageError)?;
-
-        rustfs_common::metrics::Metrics::inc_time(Metric::QuotaSync, start_time.elapsed());
-        Ok(updated_at)
-    }
-
    async fn set_quota_config_for_incarnation(
        &mut self,
        bucket: &str,
@@ -381,7 +355,6 @@ mod tests {
            quota_limit: None,
            operation_size: 1024,
            remaining: None,
-            uses_durable_reservations: false,
        };

        assert!(result.allowed);
@@ -405,13 +378,4 @@ mod tests {
        let allowed = quota.check_operation_allowed(512, 1024);
        assert!(!allowed);
    }
-
-    #[test]
-    fn legacy_quota_rejects_full_operation_while_v1_defers_net_growth() {
-        let legacy: BucketQuota = serde_json::from_str(r#"{"quota":5}"#).expect("legacy quota should parse");
-        let durable = BucketQuota::new(Some(5));
-
-        assert!(!legacy.check_operation_allowed(4, 2));
-        assert!(durable.uses_durable_reservations());
-    }
 }
@@ -13,98 +13,38 @@
 // limitations under the License.

 pub mod checker;
-pub(crate) mod reservation;

 use crate::error::Result;
 use rustfs_config::{
    QUOTA_API_PATH, QUOTA_EXCEEDED_ERROR_CODE, QUOTA_INTERNAL_ERROR_CODE, QUOTA_INVALID_CONFIG_ERROR_CODE,
    QUOTA_NOT_FOUND_ERROR_CODE,
 };
-use serde::{Deserialize, Deserializer, Serialize, Serializer, de::Error as _};
+use serde::{Deserialize, Serialize};
 use thiserror::Error;
 use time::OffsetDateTime;

 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, Default)]
 pub enum QuotaType {
-    /// Hard quota accounting.
+    /// Hard quota: reject immediately when exceeded
    #[default]
    #[serde(alias = "HARD", alias = "hard")]
    Hard,
 }

-pub(crate) const QUOTA_RESERVATION_PROTOCOL_V1: u32 = 1;
-
 /// Bucket quota configuration. quota_type defaults to Hard when omitted.
-#[derive(Debug, Default, Clone, PartialEq)]
+#[derive(Debug, Deserialize, Serialize, Default, Clone, PartialEq)]
 pub struct BucketQuota {
+    #[serde(default)]
    pub quota: Option<u64>,
    /// Defaults to Hard when missing.
+    #[serde(default)]
    pub quota_type: QuotaType,
-    /// Optional durable reservation protocol. The wire format gives older
-    /// nodes a zero hard quota so a mixed-version fleet fails closed.
-    pub reservation_protocol: Option<u32>,
    /// Timestamp when this quota configuration was set (for audit purposes)
+    #[serde(default, with = "time::serde::rfc3339::option")]
    pub created_at: Option<OffsetDateTime>,
    /// Accept updated_at for compatibility; not used.
-    pub updated_at: Option<OffsetDateTime>,
-}
-
-#[derive(Deserialize, Serialize)]
-struct BucketQuotaWire {
-    #[serde(default)]
-    quota: Option<u64>,
-    #[serde(default)]
-    quota_type: QuotaType,
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    reservation_protocol: Option<u32>,
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    reservation_quota: Option<u64>,
-    #[serde(default, with = "time::serde::rfc3339::option")]
-    created_at: Option<OffsetDateTime>,
    #[serde(default, with = "time::serde::rfc3339::option", skip_serializing_if = "Option::is_none")]
-    updated_at: Option<OffsetDateTime>,
-}
-
-impl Serialize for BucketQuota {
-    fn serialize<S>(&self, serializer: S) -> std::result::Result<S::Ok, S::Error>
-    where
-        S: Serializer,
-    {
-        let durable = self.uses_durable_reservations();
-        BucketQuotaWire {
-            quota: if durable { Some(0) } else { self.quota },
-            quota_type: self.quota_type.clone(),
-            reservation_protocol: self.reservation_protocol,
-            reservation_quota: if durable { self.quota } else { None },
-            created_at: self.created_at,
-            updated_at: self.updated_at,
-        }
-        .serialize(serializer)
-    }
-}
-
-impl<'de> Deserialize<'de> for BucketQuota {
-    fn deserialize<D>(deserializer: D) -> std::result::Result<Self, D::Error>
-    where
-        D: Deserializer<'de>,
-    {
-        let wire = BucketQuotaWire::deserialize(deserializer)?;
-        let quota = if wire.reservation_protocol == Some(QUOTA_RESERVATION_PROTOCOL_V1) {
-            Some(
-                wire.reservation_quota
-                    .ok_or_else(|| D::Error::custom("reservation_quota is required for reservation protocol v1"))?,
-            )
-        } else {
-            wire.quota
-        };
-        Ok(Self {
-            quota,
-            quota_type: wire.quota_type,
-            reservation_protocol: wire.reservation_protocol,
-            created_at: wire.created_at,
-            updated_at: wire.updated_at,
-        })
-    }
+    pub updated_at: Option<OffsetDateTime>,
 }

 impl BucketQuota {
@@ -123,7 +63,6 @@ impl BucketQuota {
        Self {
            quota,
            quota_type: QuotaType::Hard,
-            reservation_protocol: quota.map(|_| QUOTA_RESERVATION_PROTOCOL_V1),
            created_at: Some(now),
            updated_at: None,
        }
@@ -133,19 +72,7 @@ impl BucketQuota {
        self.quota
    }

-    pub fn uses_durable_reservations(&self) -> bool {
-        self.reservation_protocol == Some(QUOTA_RESERVATION_PROTOCOL_V1)
-    }
-
-    pub fn has_unsupported_reservation_protocol(&self) -> bool {
-        self.reservation_protocol
-            .is_some_and(|version| version != QUOTA_RESERVATION_PROTOCOL_V1)
-    }
-
    pub fn check_operation_allowed(&self, current_usage: u64, operation_size: u64) -> bool {
-        if operation_size == 0 {
-            return true;
-        }
        if let Some(quota_limit) = self.quota {
            current_usage.saturating_add(operation_size) <= quota_limit
        } else {
@@ -167,7 +94,6 @@ pub struct QuotaCheckResult {
    pub quota_limit: Option<u64>,
    pub operation_size: u64,
    pub remaining: Option<u64>,
-    pub uses_durable_reservations: bool,
 }

 #[derive(Debug)]
@@ -284,59 +210,7 @@ mod tests {
        let buf = q.marshal_msg().expect("marshal");
        let restored = BucketQuota::unmarshal(&buf).expect("unmarshal");
        assert_eq!(q.quota, restored.quota);
-        assert_eq!(restored.quota_type, QuotaType::Hard);
-        assert_eq!(restored.reservation_protocol, Some(QUOTA_RESERVATION_PROTOCOL_V1));
-    }
-
-    #[test]
-    fn clearing_quota_keeps_the_legacy_compatible_type() {
-        let quota = BucketQuota::new(None);
-
-        assert_eq!(quota.quota_type, QuotaType::Hard);
-        assert_eq!(quota.reservation_protocol, None);
-        assert!(!quota.uses_durable_reservations());
-    }
-
-    #[test]
-    fn durable_quota_makes_legacy_nodes_fail_closed() {
-        let json = serde_json::to_vec(&BucketQuota::new(Some(2048))).expect("durable quota should serialize");
-        let quota: BucketQuota = serde_json::from_slice(&json).expect("current quota version should parse");
-        assert!(quota.uses_durable_reservations());
-        assert_eq!(quota.quota, Some(2048));
-
-        #[derive(Deserialize)]
-        enum LegacyQuotaType {
-            Hard,
-        }
-        #[derive(Deserialize)]
-        struct LegacyBucketQuota {
-            #[allow(dead_code)]
-            quota: Option<u64>,
-            #[allow(dead_code)]
-            quota_type: LegacyQuotaType,
-        }
-        let legacy = serde_json::from_slice::<LegacyBucketQuota>(&json)
-            .expect("legacy readers should ignore the reservation protocol field");
-        assert_eq!(legacy.quota, Some(0));
-        assert!(matches!(legacy.quota_type, LegacyQuotaType::Hard));
-    }
-
-    #[test]
-    fn unknown_reservation_protocol_does_not_activate_v1() {
-        let quota: BucketQuota =
-            serde_json::from_str(r#"{"quota":0,"quota_type":"Hard","reservation_protocol":2,"reservation_quota":2048}"#)
-                .expect("future protocol should remain parseable");
-
-        assert!(!quota.uses_durable_reservations());
-        assert!(quota.has_unsupported_reservation_protocol());
-    }
-
-    #[test]
-    fn reservation_protocol_v1_requires_reservation_quota() {
-        let err = serde_json::from_str::<BucketQuota>(r#"{"quota":0,"quota_type":"Hard","reservation_protocol":1}"#)
-            .expect_err("v1 without its authoritative quota must fail closed");
-
-        assert!(err.to_string().contains("reservation_quota is required"));
+        assert_eq!(q.quota_type, restored.quota_type);
    }

    /// unmarshal accepts format without quota_type
@@ -13,6 +13,7 @@
 // limitations under the License.

 // #730: cluster/RPC migration leaves transport capabilities staged for upcoming owners.
+#![allow(dead_code)]

 mod control_plane;
 pub(crate) mod rpc;
@@ -256,7 +256,6 @@ impl<S> ReplayScopeChannel<S> {
    }
 }

-#[allow(dead_code, reason = "replay-state probe asserted by this file's tests (backlog#1823)")]
 fn peer_replay_state(audience: &str) -> PeerReplayState {
    PEER_REPLAY_STATES
        .lock()
@@ -31,7 +31,7 @@ use rustfs_config::{
    DEFAULT_INTERNODE_DATA_TRANSPORT, ENV_RUSTFS_INTERNODE_DATA_TRANSPORT, INTERNODE_DATA_TRANSPORT_TCP,
    KNOWN_INTERNODE_DATA_TRANSPORT_BACKENDS,
 };
-use rustfs_rio::{ChunkReaderBox, HttpChunkReader, HttpReader, HttpWriter};
+use rustfs_rio::{HttpReader, HttpWriter};
 use sha2::{Digest, Sha256};
 use std::collections::HashMap;
 use std::future::Future;
@@ -43,10 +43,6 @@ use tokio::io::{AsyncReadExt, AsyncWrite};
 use tokio::sync::OnceCell;
 use uuid::Uuid;

-#[allow(
-    dead_code,
-    reason = "live in the cfg(not(test)) half of build_internode_data_transport_from_env (backlog#1823)"
-)]
 static INTERNODE_DATA_TRANSPORT: OnceLock<std::result::Result<Arc<dyn InternodeDataTransport>, String>> = OnceLock::new();

 const READ_FILE_STREAM_PATH: &str = "/rustfs/rpc/read_file_stream";
@@ -138,10 +134,6 @@ fn put_file_capability_status_is_legacy(status: u16) -> bool {
 }

 #[derive(Debug, Clone, Copy, Eq, PartialEq)]
-#[allow(
-    dead_code,
-    reason = "capability-negotiation seam; constructed only by transport test doubles (backlog#1823)"
-)]
 pub struct InternodeDataTransportCapabilities {
    /// Backend can open a streaming remote disk reader.
    pub streaming_read: bool,
@@ -158,10 +150,6 @@ pub struct InternodeDataTransportCapabilities {
 }

 impl InternodeDataTransportCapabilities {
-    #[allow(
-        dead_code,
-        reason = "capability-negotiation seam; used by transport test doubles (backlog#1823)"
-    )]
    pub const fn tcp_http() -> Self {
        Self {
            streaming_read: true,
@@ -233,11 +221,6 @@ pub struct NsScannerCapabilityRequest {
 #[async_trait]
 pub trait InternodeDataTransport: Send + Sync + std::fmt::Debug {
    async fn open_read(&self, request: ReadStreamRequest) -> Result<FileReader>;
-    /// Opens an owned-chunk stream when this transport can retain receive-buffer
-    /// ownership. `None` preserves the established `open_read` fallback.
-    async fn open_read_chunks(&self, _request: ReadStreamRequest) -> Result<Option<ChunkReaderBox>> {
-        Ok(None)
-    }
    async fn open_write(&self, request: WriteStreamRequest) -> Result<FileWriter>;
    async fn open_walk_dir(&self, request: WalkDirStreamRequest) -> Result<FileReader>;
    async fn open_ns_scanner(&self, _request: NsScannerStreamRequest) -> Result<FileReader> {
@@ -246,12 +229,7 @@ pub trait InternodeDataTransport: Send + Sync + std::fmt::Debug {
    async fn probe_ns_scanner(&self, _request: NsScannerCapabilityRequest) -> Result<Uuid> {
        Err(Error::MethodNotAllowed)
    }
-    // Interface facet nobody calls yet: every transport implements both, but no
-    // caller negotiates on them. Kept for the internode transport split
-    // (backlog#1350); deleting them would delete the seam and six impls.
-    #[allow(dead_code, reason = "unused capability-negotiation facet (backlog#1823)")]
    fn name(&self) -> &'static str;
-    #[allow(dead_code, reason = "unused capability-negotiation facet (backlog#1823)")]
    fn capabilities(&self) -> InternodeDataTransportCapabilities;
 }

@@ -269,15 +247,6 @@ impl InternodeDataTransport for TcpHttpInternodeDataTransport {
        ))
    }

-    async fn open_read_chunks(&self, request: ReadStreamRequest) -> Result<Option<ChunkReaderBox>> {
-        let url = build_read_file_stream_url(&request);
-        let mut headers = json_headers();
-        build_auth_headers(&url, &Method::GET, &mut headers)?;
-        Ok(Some(Box::new(
-            HttpChunkReader::new_with_stall_timeout(url, Method::GET, headers, None, request.stall_timeout).await?,
-        )))
-    }
-
    async fn open_write(&self, request: WriteStreamRequest) -> Result<FileWriter> {
        let server_epoch = self.put_file_auth_capability(&request.endpoint).await?;
        let nonce = server_epoch.map(|_| Uuid::new_v4());
@@ -687,10 +656,6 @@ fn build_internode_data_transport_result(
    }
 }

-#[allow(
-    dead_code,
-    reason = "live in the cfg(test) half of build_internode_data_transport_from_env, which bypasses the process static (backlog#1823)"
-)]
 pub fn build_internode_data_transport(configured_transport: Option<&str>) -> Result<Arc<dyn InternodeDataTransport>> {
    build_internode_data_transport_result(configured_transport).map_err(Error::other)
 }
@@ -248,16 +248,6 @@ fn decode_remote_version_state_capability(expected_member: &str, result: &[u8])
    Ok(server_epoch)
 }

-fn decode_cross_pool_fence_capability(expected_member: &str, result: &[u8]) -> Result<(u32, Uuid)> {
-    let version = result
-        .get(..4)
-        .and_then(|value| value.try_into().ok())
-        .map(u32::from_be_bytes)
-        .ok_or_else(|| Error::other("peer returned an invalid cross-pool fence capability version"))?;
-    let epoch = decode_remote_version_state_capability(expected_member, &result[4..])?;
-    Ok((version, epoch))
-}
-
 #[derive(Clone, Debug)]
 pub struct PeerLiveEventsBatch {
    pub events: Vec<u8>,
@@ -1298,16 +1288,6 @@ impl PeerRestClient {
        Ok((self.topology_member.clone(), epoch))
    }

-    pub async fn probe_cross_pool_fence(&self, topology_fingerprint: String) -> Result<(String, u32, Uuid)> {
-        let mut probe = rustfs_protos::CROSS_POOL_FENCE_CAPABILITY_PROBE_PREFIX.to_vec();
-        probe.extend_from_slice(Uuid::new_v4().as_bytes());
-        let result = self
-            .heal_control(rustfs_protos::HEAL_CONTROL_PROTOCOL_VERSION, topology_fingerprint, probe)
-            .await?;
-        let (supported_version, epoch) = decode_cross_pool_fence_capability(&self.topology_member, &result)?;
-        Ok((self.topology_member.clone(), supported_version, epoch))
-    }
-
    pub async fn load_bucket_metadata(&self, bucket: &str, scanner_maintenance_change: bool) -> Result<()> {
        self.finalize_result(
            async {
@@ -2758,24 +2738,6 @@ mod tests {
        assert!(decode_remote_version_state_capability("node-a:9000", &nil).is_err());
    }

-    #[test]
-    fn cross_pool_fence_capability_decoder_fails_closed() {
-        let epoch = Uuid::new_v4();
-        let result = rustfs_protos::encode_cross_pool_fence_capability(1, "node-a:9000", epoch.as_bytes())
-            .expect("small capability response should encode");
-        assert_eq!(
-            decode_cross_pool_fence_capability("node-a:9000", &result).expect("valid capability should decode"),
-            (1, epoch)
-        );
-        for malformed in [&[][..], &[0, 0, 0][..], &result[..result.len() - 1]] {
-            assert!(decode_cross_pool_fence_capability("node-a:9000", malformed).is_err());
-        }
-        assert!(decode_cross_pool_fence_capability("node-b:9000", &result).is_err());
-        let nil = rustfs_protos::encode_cross_pool_fence_capability(1, "node-a:9000", Uuid::nil().as_bytes())
-            .expect("small capability response should encode");
-        assert!(decode_cross_pool_fence_capability("node-a:9000", &nil).is_err());
-    }
-
    struct TierMutationResponseFixture<'a> {
        version: u32,
        phase: TierMutationRpcPhase,
@@ -854,6 +854,7 @@ impl PeerS3Client for LocalPeerS3Client {

 #[derive(Debug)]
 pub struct RemotePeerS3Client {
+    pub node: Option<Node>,
    pub pools: Option<Vec<usize>>,
    addr: String,
    /// Health tracker for connection monitoring
@@ -885,6 +886,7 @@ impl RemotePeerS3Client {
    pub fn new(node: Option<Node>, pools: Option<Vec<usize>>) -> Self {
        let addr = node.as_ref().map(|v| v.url.to_string()).unwrap_or_default();
        let client = Self {
+            node,
            pools,
            addr,
            health: Arc::new(DiskHealthTracker::new()),
@@ -903,6 +905,10 @@ impl RemotePeerS3Client {
            .map_err(|err| Error::other(format!("can not get client, err: {err}")))
    }

+    pub fn get_addr(&self) -> String {
+        self.addr.clone()
+    }
+
    /// Start health monitoring for the remote peer
    fn start_health_monitoring(&self) {
        let health = Arc::clone(&self.health);
@@ -1202,10 +1208,6 @@ impl PeerS3Client for RemotePeerS3Client {
    }
 }

-#[allow(
-    dead_code,
-    reason = "local bucket-heal path reached only by this file's tests (backlog#1823)"
-)]
 pub async fn heal_bucket_local(bucket: &str, opts: &HealOpts) -> Result<HealResultItem> {
    let disks = clone_drives().await;
    heal_bucket_local_on_disks(bucket, opts, disks).await
@@ -1402,10 +1404,6 @@ pub(crate) async fn heal_bucket_local_on_disks(
    }
 }

-#[allow(
-    dead_code,
-    reason = "reached only through heal_bucket_local, which only tests call (backlog#1823)"
-)]
 async fn clone_drives() -> Vec<Option<DiskStore>> {
    runtime_sources::local_disk_entries().await
 }
@@ -1587,7 +1585,15 @@ mod tests {
    }

    fn test_remote_peer(addr: &str) -> RemotePeerS3Client {
+        let node = Node {
+            url: url::Url::parse(addr).expect("test peer URL should parse"),
+            pools: vec![0],
+            is_local: false,
+            grid_host: addr.to_string(),
+        };
+
        RemotePeerS3Client {
+            node: Some(node),
            pools: Some(vec![0]),
            addr: addr.to_string(),
            health: Arc::new(DiskHealthTracker::new()),
@@ -522,33 +522,6 @@ impl RemoteDisk {
        }
    }

-    async fn open_read_chunks_with_retry(&self, request: ReadStreamRequest) -> Result<Option<rustfs_rio::ChunkReaderBox>> {
-        let mut attempt = 1;
-        let mut last_retry_classification = None;
-        loop {
-            match self.data_transport.open_read_chunks(request.clone()).await {
-                Ok(reader) => {
-                    if attempt > 1
-                        && let Some(classification) = last_retry_classification
-                    {
-                        crate::cluster::rpc::runtime_sources::record_remote_disk_open_read_retry_success(classification);
-                    }
-                    return Ok(reader);
-                }
-                Err(err) if attempt < REMOTE_DISK_OPEN_READ_MAX_ATTEMPTS && Self::is_retryable_open_read_error(&err) => {
-                    if let Some(classification) = err.internode_http_error_kind() {
-                        let classification = classification.metric_label();
-                        crate::cluster::rpc::runtime_sources::record_remote_disk_open_read_retry(classification);
-                        last_retry_classification = Some(classification);
-                    }
-                    tokio::time::sleep(REMOTE_DISK_OPEN_READ_RETRY_BACKOFF).await;
-                    attempt += 1;
-                }
-                Err(err) => return Err(err),
-            }
-        }
-    }
-
    pub fn record_capacity_probe(&self, total: u64, used: u64, free: u64) {
        self.health.record_capacity_probe(total, used, free);
    }
@@ -873,49 +846,31 @@ impl RemoteDisk {
    /// default to 1 (see [`internode_idempotent_read_retries`]). MUST NOT be used for write/lock
    /// RPCs — those must never auto-retry (quorum/idempotency safety). The `operation` closure is
    /// re-invoked per attempt, so it must be `Fn` (rebuild the request from borrowed inputs, do not
-    /// move captured state out). Attempts and backoff share one total timeout budget.
+    /// move captured state out).
    async fn execute_read_with_retry<T, F, Fut>(&self, op: &'static str, operation: F, timeout_duration: Duration) -> Result<T>
    where
        F: Fn() -> Fut,
        Fut: std::future::Future<Output = Result<T>>,
    {
-        let deadline = (!timeout_duration.is_zero()).then(|| {
-            time::Instant::now()
-                .checked_add(timeout_duration)
-                .unwrap_or_else(|| time::sleep(timeout_duration).deadline())
-        });
        let max_retries = internode_idempotent_read_retries();
        let mut attempt = 0usize;
        loop {
-            let attempt_timeout = deadline
-                .map(|deadline| deadline.saturating_duration_since(time::Instant::now()))
-                .unwrap_or(Duration::ZERO);
-            if deadline.is_some() && attempt_timeout.is_zero() {
-                self.record_timeout(op, timeout_duration);
-                return Err(DiskError::Timeout);
-            }
-
+            // Only the final attempt marks the disk faulty / evicts the channel. Earlier retries
+            // ignore the failure, so a transient error cannot flip the disk into a faulty
+            // short-circuit (which would defeat the retry) or over-count failures.
            let health_action = if attempt >= max_retries {
                FailureHealthAction::MarkFailure
            } else {
                FailureHealthAction::IgnoreFailure
            };
            match self
-                .execute_with_timeout_for_op_and_health_action(op, &operation, attempt_timeout, health_action)
+                .execute_with_timeout_for_op_and_health_action(op, &operation, timeout_duration, health_action)
                .await
            {
                Err(err) if attempt < max_retries && is_network_like_disk_error(&err) => {
-                    if matches!(err, DiskError::Timeout) && deadline.is_some_and(|deadline| time::Instant::now() >= deadline) {
-                        self.mark_faulty("read_operation_deadline");
-                        return Err(err);
-                    }
                    attempt += 1;
                    let backoff = REMOTE_DISK_READ_RETRY_BASE_BACKOFF
                        .saturating_mul(1u32 << u32::try_from(attempt - 1).unwrap_or(4).min(4));
-                    if deadline.is_some_and(|deadline| deadline.saturating_duration_since(time::Instant::now()) <= backoff) {
-                        attempt = max_retries;
-                        continue;
-                    }
                    debug!(
                        endpoint = %self.endpoint,
                        addr = %self.addr,
@@ -923,17 +878,7 @@ impl RemoteDisk {
                        attempt,
                        "retrying idempotent read-only RPC after transient network error"
                    );
-                    if let Some(deadline) = deadline {
-                        if time::timeout_at(deadline, time::sleep(backoff)).await.is_err() {
-                            self.record_timeout(op, timeout_duration);
-                            return Err(DiskError::Timeout);
-                        }
-                    } else {
-                        time::sleep(backoff).await;
-                    }
-                    if self.health.is_faulty() {
-                        return Err(DiskError::FaultyDisk);
-                    }
+                    tokio::time::sleep(backoff).await;
                }
                other => return other,
            }
@@ -1012,35 +957,32 @@ impl RemoteDisk {
                operation_result
            }
            Err(_) => {
-                self.record_timeout(op, timeout_duration);
+                // Timeout occurred, mark disk as potentially faulty
+                counter!(
+                    "rustfs_drive_op_timeout_total",
+                    "endpoint" => self.endpoint.to_string(),
+                    "op" => op.to_string()
+                )
+                .increment(1);
                if failure_health_action == FailureHealthAction::MarkFailure {
                    self.mark_faulty_and_evict("operation_timeout").await;
                }
+                warn!(
+                    event = EVENT_REMOTE_DISK_RPC,
+                    component = LOG_COMPONENT_ECSTORE,
+                    subsystem = LOG_SUBSYSTEM_REMOTE_DISK,
+                    endpoint = %self.endpoint,
+                    addr = %self.addr,
+                    op,
+                    timeout_ms = timeout_duration.as_millis(),
+                    state = "timeout",
+                    "Remote disk operation timed out"
+                );
                Err(DiskError::Timeout)
            }
        }
    }

-    fn record_timeout(&self, op: &'static str, timeout_duration: Duration) {
-        counter!(
-            "rustfs_drive_op_timeout_total",
-            "endpoint" => self.endpoint.to_string(),
-            "op" => op.to_string()
-        )
-        .increment(1);
-        warn!(
-            event = EVENT_REMOTE_DISK_RPC,
-            component = LOG_COMPONENT_ECSTORE,
-            subsystem = LOG_SUBSYSTEM_REMOTE_DISK,
-            endpoint = %self.endpoint,
-            addr = %self.addr,
-            op,
-            timeout_ms = timeout_duration.as_millis(),
-            state = "timeout",
-            "Remote disk operation timed out"
-        );
-    }
-
    async fn handle_network_like_error<T>(
        &self,
        op: &'static str,
@@ -1074,7 +1016,7 @@ impl RemoteDisk {
        }
    }

-    fn mark_faulty(&self, reason: &'static str) -> bool {
+    async fn mark_faulty_and_evict(&self, reason: &'static str) {
        let previous_state = self.runtime_state();
        let transitioned_to_offline = self.mark_suspect_or_offline(reason);
        let state = self.runtime_state();
@@ -1111,12 +1053,6 @@ impl RemoteDisk {
                    "Remote disk marked suspect"
                );
            }
-        }
-        state != previous_state
-    }
-
-    async fn mark_faulty_and_evict(&self, reason: &'static str) {
-        if self.mark_faulty(reason) {
            counter!(
                "rustfs_drive_connection_evict_total",
                "endpoint" => self.endpoint.to_string(),
@@ -1359,71 +1295,6 @@ fn validate_decoded_file_info(file_info: &FileInfo) -> Result<()> {
    file_info.validate_for_metadata_read().map_err(Into::into)
 }

-impl RemoteDisk {
-    #[tracing::instrument(level = "trace", skip_all)]
-    pub(crate) async fn rename_data_borrowed(
-        &self,
-        src_volume: &str,
-        src_path: &str,
-        fi: &FileInfo,
-        dst_volume: &str,
-        dst_path: &str,
-    ) -> Result<RenameDataResp> {
-        trace!(
-            event = EVENT_REMOTE_DISK_RPC,
-            component = LOG_COMPONENT_ECSTORE,
-            subsystem = LOG_SUBSYSTEM_REMOTE_DISK,
-            endpoint = %self.endpoint,
-            src_volume,
-            src_path,
-            dst_volume,
-            dst_path,
-            op = "rename_data",
-            state = "started",
-            "Remote disk RPC started"
-        );
-
-        self.execute_with_timeout_for_op(
-            "rename_data",
-            || async {
-                let file_info = compat_json(fi)?;
-                let file_info_bin = encode_file_info_msgpack(fi)?;
-                let mut client = self
-                    .get_client()
-                    .await
-                    .map_err(|err| Error::other(format!("can not get client, err: {err}")))?;
-                let mut request = Request::new(RenameDataRequest {
-                    disk: self.endpoint.to_string(),
-                    src_volume: src_volume.to_string(),
-                    src_path: src_path.to_string(),
-                    file_info,
-                    dst_volume: dst_volume.to_string(),
-                    dst_path: dst_path.to_string(),
-                    file_info_bin: file_info_bin.into(),
-                });
-                let canonical_body = rustfs_protos::canonical_rename_data_request_body(request.get_ref());
-                attach_mutation_body_digest(&mut request, canonical_body, "rename_data")?;
-
-                let response = client.rename_data(request).await?.into_inner();
-
-                if !response.success {
-                    return Err(response.error.unwrap_or_default().into());
-                }
-
-                let rename_data_resp = decode_msgpack_or_json::<RenameDataResp>(
-                    &response.rename_data_resp_bin,
-                    &response.rename_data_resp,
-                    "RenameDataResp",
-                )?;
-
-                Ok(rename_data_resp)
-            },
-            get_max_timeout_duration(),
-        )
-        .await
-    }
-}
-
 #[async_trait::async_trait]
 impl DiskAPI for RemoteDisk {
    #[tracing::instrument(level = "trace", skip_all)]
@@ -2197,7 +2068,7 @@ impl DiskAPI for RemoteDisk {

                Ok(file_info)
            },
-            get_drive_metadata_timeout(),
+            get_max_timeout_duration(),
        )
        .await
    }
@@ -2349,8 +2220,58 @@ impl DiskAPI for RemoteDisk {
        dst_volume: &str,
        dst_path: &str,
    ) -> Result<RenameDataResp> {
-        self.rename_data_borrowed(src_volume, src_path, &fi, dst_volume, dst_path)
-            .await
+        trace!(
+            event = EVENT_REMOTE_DISK_RPC,
+            component = LOG_COMPONENT_ECSTORE,
+            subsystem = LOG_SUBSYSTEM_REMOTE_DISK,
+            endpoint = %self.endpoint,
+            src_volume,
+            src_path,
+            dst_volume,
+            dst_path,
+            op = "rename_data",
+            state = "started",
+            "Remote disk RPC started"
+        );
+
+        self.execute_with_timeout_for_op(
+            "rename_data",
+            || async {
+                let file_info = compat_json(&fi)?;
+                let file_info_bin = encode_file_info_msgpack(&fi)?;
+                let mut client = self
+                    .get_client()
+                    .await
+                    .map_err(|err| Error::other(format!("can not get client, err: {err}")))?;
+                let mut request = Request::new(RenameDataRequest {
+                    disk: self.endpoint.to_string(),
+                    src_volume: src_volume.to_string(),
+                    src_path: src_path.to_string(),
+                    file_info,
+                    dst_volume: dst_volume.to_string(),
+                    dst_path: dst_path.to_string(),
+                    file_info_bin: file_info_bin.into(),
+                });
+                let canonical_body = rustfs_protos::canonical_rename_data_request_body(request.get_ref());
+                attach_mutation_body_digest(&mut request, canonical_body, "rename_data")?;
+
+                let response = client.rename_data(request).await?.into_inner();
+
+                if !response.success {
+                    return Err(response.error.unwrap_or_default().into());
+                }
+
+                let rename_data_resp = decode_msgpack_or_json::<RenameDataResp>(
+                    &response.rename_data_resp_bin,
+                    &response.rename_data_resp,
+                    "RenameDataResp",
+                )?;
+
+                Ok(rename_data_resp)
+            },
+            get_max_timeout_duration(),
+        )
+        .await
    }

    #[tracing::instrument(level = "trace", skip_all)]
@@ -2496,30 +2417,6 @@ impl DiskAPI for RemoteDisk {
        .await
    }

-    async fn read_file_stream_chunks(
-        &self,
-        volume: &str,
-        path: &str,
-        offset: usize,
-        length: usize,
-    ) -> Result<Option<rustfs_rio::ChunkReaderBox>> {
-        if self.health.is_faulty() {
-            return Err(DiskError::FaultyDisk);
-        }
-        let disk = self.disk_ref().await;
-        let stall_timeout = get_object_disk_read_timeout();
-        self.open_read_chunks_with_retry(ReadStreamRequest {
-            endpoint: self.endpoint.grid_host(),
-            disk,
-            volume: volume.to_string(),
-            path: path.to_string(),
-            offset,
-            length,
-            stall_timeout: (!stall_timeout.is_zero()).then_some(stall_timeout),
-        })
-        .await
-    }
-
    /// Buffered read for remote disks.
    /// The transport stream is collected into owned Bytes for caller sharing.
    #[tracing::instrument(level = "trace", skip_all)]
@@ -5197,452 +5094,6 @@ mod tests {
        );
    }

-    #[tokio::test(start_paused = true)]
-    #[serial(remote_disk_read_retry)]
-    async fn execute_read_with_retry_reset_during_backoff_preserves_recovery() {
-        let remote_disk = Arc::new(new_remote_disk_with_transport(Arc::new(RecordingInternodeDataTransport::default())).await);
-        let attempts = Arc::new(std::sync::atomic::AtomicUsize::new(0));
-        let first_attempt = Arc::new(tokio::sync::Notify::new());
-        let started = time::Instant::now();
-
-        let task_disk = Arc::clone(&remote_disk);
-        let task_attempts = Arc::clone(&attempts);
-        let task_first_attempt = Arc::clone(&first_attempt);
-        let task = tokio::spawn(async move {
-            task_disk
-                .execute_read_with_retry(
-                    "read_version",
-                    move || {
-                        let attempt = task_attempts.fetch_add(1, Ordering::SeqCst);
-                        let first_attempt = Arc::clone(&task_first_attempt);
-                        async move {
-                            if attempt == 0 {
-                                time::sleep(Duration::from_millis(20)).await;
-                                first_attempt.notify_one();
-                                return Err::<(), Error>(DiskError::Io(std_io::Error::new(
-                                    std_io::ErrorKind::ConnectionRefused,
-                                    "connection refused",
-                                )));
-                            }
-                            Ok(())
-                        }
-                    },
-                    Duration::from_millis(100),
-                )
-                .await
-        });
-
-        first_attempt.notified().await;
-        tokio::task::yield_now().await;
-        remote_disk.health.reset_for_store_init_retry(&remote_disk.endpoint);
-        let channel = TonicEndpoint::from_shared(remote_disk.addr.clone())
-            .expect("remote disk address should parse")
-            .connect_lazy();
-        runtime_sources::cache_test_node_channel(remote_disk.addr.clone(), channel).await;
-        task.await
-            .expect("retry task should finish")
-            .expect("the retry should succeed after the health reset");
-
-        assert_eq!(attempts.load(Ordering::SeqCst), 2);
-        assert_eq!(started.elapsed(), Duration::from_millis(70));
-        assert_eq!(
-            remote_disk.health.waiting_count(),
-            0,
-            "health reset must not underflow the waiting counter"
-        );
-        assert_eq!(remote_disk.runtime_state(), RuntimeDriveHealthState::Online);
-        assert!(
-            runtime_sources::test_node_channel_is_cached(&remote_disk.addr).await,
-            "a recovered channel must survive the retry backoff"
-        );
-        remote_disk.cancel_token.cancel();
-    }
-
-    #[tokio::test(start_paused = true)]
-    #[serial(remote_disk_read_retry)]
-    async fn execute_read_with_retry_still_retries_within_shared_deadline() {
-        let remote_disk = new_remote_disk_with_transport(Arc::new(RecordingInternodeDataTransport::default())).await;
-        let attempts = Arc::new(std::sync::atomic::AtomicUsize::new(0));
-        let channel = TonicEndpoint::from_shared(remote_disk.addr.clone())
-            .expect("remote disk address should parse")
-            .connect_lazy();
-        runtime_sources::cache_test_node_channel(remote_disk.addr.clone(), channel).await;
-
-        remote_disk
-            .execute_read_with_retry(
-                "read_version",
-                || {
-                    let attempt = attempts.fetch_add(1, Ordering::SeqCst);
-                    async move {
-                        if attempt == 0 {
-                            return Err::<(), Error>(DiskError::Io(std_io::Error::new(
-                                std_io::ErrorKind::ConnectionReset,
-                                "connection reset",
-                            )));
-                        }
-                        Ok(())
-                    }
-                },
-                Duration::from_millis(100),
-            )
-            .await
-            .expect("a retry that fits the shared deadline should succeed");
-
-        assert_eq!(attempts.load(Ordering::SeqCst), 2);
-        assert_eq!(remote_disk.runtime_state(), RuntimeDriveHealthState::Online);
-        assert!(runtime_sources::test_node_channel_is_cached(&remote_disk.addr).await);
-        remote_disk.cancel_token.cancel();
-    }
-
-    #[tokio::test(start_paused = true)]
-    #[serial(remote_disk_read_retry)]
-    async fn execute_read_with_retry_uses_remaining_budget_for_final_attempt() {
-        let remote_disk = new_remote_disk_with_transport(Arc::new(RecordingInternodeDataTransport::default())).await;
-        let attempts = Arc::new(std::sync::atomic::AtomicUsize::new(0));
-        let started = time::Instant::now();
-        let channel = TonicEndpoint::from_shared(remote_disk.addr.clone())
-            .expect("remote disk address should parse")
-            .connect_lazy();
-        runtime_sources::cache_test_node_channel(remote_disk.addr.clone(), channel).await;
-
-        let err = remote_disk
-            .execute_read_with_retry(
-                "read_version",
-                || {
-                    let attempt = attempts.fetch_add(1, Ordering::SeqCst);
-                    async move {
-                        if attempt == 0 {
-                            time::sleep(Duration::from_millis(20)).await;
-                            return Err::<(), Error>(DiskError::Io(std_io::Error::new(
-                                std_io::ErrorKind::ConnectionRefused,
-                                "connection refused",
-                            )));
-                        }
-                        std::future::pending::<Result<()>>().await
-                    }
-                },
-                Duration::from_millis(100),
-            )
-            .await
-            .expect_err("the final retry should consume only the remaining total budget");
-
-        assert_eq!(err, DiskError::Timeout);
-        assert_eq!(attempts.load(Ordering::SeqCst), 2);
-        assert_eq!(started.elapsed(), Duration::from_millis(100));
-        assert_eq!(remote_disk.runtime_state(), RuntimeDriveHealthState::Suspect);
-        assert!(!runtime_sources::test_node_channel_is_cached(&remote_disk.addr).await);
-        remote_disk.cancel_token.cancel();
-    }
-
-    #[tokio::test(start_paused = true)]
-    #[serial(remote_disk_read_retry)]
-    async fn execute_read_with_retry_uses_final_attempt_at_exact_backoff_boundary() {
-        let remote_disk = new_remote_disk_with_transport(Arc::new(RecordingInternodeDataTransport::default())).await;
-        let attempts = Arc::new(std::sync::atomic::AtomicUsize::new(0));
-        let started = time::Instant::now();
-
-        let err = remote_disk
-            .execute_read_with_retry(
-                "read_version",
-                || {
-                    let attempt = attempts.fetch_add(1, Ordering::SeqCst);
-                    async move {
-                        if attempt == 0 {
-                            time::sleep(Duration::from_millis(50)).await;
-                            return Err::<(), Error>(DiskError::Io(std_io::Error::new(
-                                std_io::ErrorKind::ConnectionRefused,
-                                "connection refused",
-                            )));
-                        }
-                        std::future::pending::<Result<()>>().await
-                    }
-                },
-                Duration::from_millis(100),
-            )
-            .await
-            .expect_err("the exact backoff boundary should be reserved for a final attempt");
-
-        assert_eq!(err, DiskError::Timeout);
-        assert_eq!(attempts.load(Ordering::SeqCst), 2);
-        assert_eq!(started.elapsed(), Duration::from_millis(100));
-        assert_eq!(remote_disk.runtime_state(), RuntimeDriveHealthState::Suspect);
-        remote_disk.cancel_token.cancel();
-    }
-
-    #[tokio::test(start_paused = true)]
-    #[serial(remote_disk_read_retry)]
-    async fn execute_read_with_retry_uses_final_attempt_below_backoff_budget() {
-        let remote_disk = new_remote_disk_with_transport(Arc::new(RecordingInternodeDataTransport::default())).await;
-        let attempts = Arc::new(std::sync::atomic::AtomicUsize::new(0));
-        let started = time::Instant::now();
-
-        let err = remote_disk
-            .execute_read_with_retry(
-                "read_version",
-                || {
-                    let attempt = attempts.fetch_add(1, Ordering::SeqCst);
-                    async move {
-                        if attempt == 0 {
-                            time::sleep(Duration::from_millis(80)).await;
-                            return Err::<(), Error>(DiskError::Io(std_io::Error::new(
-                                std_io::ErrorKind::ConnectionRefused,
-                                "connection refused",
-                            )));
-                        }
-                        std::future::pending::<Result<()>>().await
-                    }
-                },
-                Duration::from_millis(100),
-            )
-            .await
-            .expect_err("remaining budget below backoff should be reserved for a final attempt");
-
-        assert_eq!(err, DiskError::Timeout);
-        assert_eq!(attempts.load(Ordering::SeqCst), 2);
-        assert_eq!(started.elapsed(), Duration::from_millis(100));
-        assert_eq!(remote_disk.runtime_state(), RuntimeDriveHealthState::Suspect);
-        remote_disk.cancel_token.cancel();
-    }
-
-    #[tokio::test(start_paused = true)]
-    #[serial(remote_disk_read_retry)]
-    async fn execute_read_with_retry_zero_timeout_disables_the_deadline() {
-        let remote_disk = new_remote_disk_with_transport(Arc::new(RecordingInternodeDataTransport::default())).await;
-        let attempts = Arc::new(std::sync::atomic::AtomicUsize::new(0));
-        let started = time::Instant::now();
-
-        remote_disk
-            .execute_read_with_retry(
-                "read_version",
-                || {
-                    let attempt = attempts.fetch_add(1, Ordering::SeqCst);
-                    async move {
-                        if attempt == 0 {
-                            return Err::<(), Error>(DiskError::Io(std_io::Error::new(
-                                std_io::ErrorKind::ConnectionReset,
-                                "connection reset",
-                            )));
-                        }
-                        Ok(())
-                    }
-                },
-                Duration::ZERO,
-            )
-            .await
-            .expect("zero timeout should allow a retry without a deadline");
-
-        assert_eq!(attempts.load(Ordering::SeqCst), 2);
-        assert_eq!(started.elapsed(), REMOTE_DISK_READ_RETRY_BASE_BACKOFF);
-        remote_disk.cancel_token.cancel();
-    }
-
-    #[tokio::test]
-    #[serial(remote_disk_read_retry)]
-    async fn execute_read_with_retry_accepts_max_metadata_timeout() {
-        temp_env::async_with_vars([(rustfs_config::ENV_DRIVE_METADATA_TIMEOUT_SECS, Some(u64::MAX.to_string()))], async {
-            let remote_disk = new_remote_disk_with_transport(Arc::new(RecordingInternodeDataTransport::default())).await;
-
-            remote_disk
-                .execute_read_with_retry("read_version", || async { Ok::<(), Error>(()) }, get_drive_metadata_timeout())
-                .await
-                .expect("the maximum configured metadata timeout must not panic");
-
-            remote_disk.cancel_token.cancel();
-        })
-        .await;
-    }
-
-    #[tokio::test(start_paused = true)]
-    #[serial(remote_disk_read_retry)]
-    async fn execute_read_with_retry_zero_retries_runs_once() {
-        temp_env::async_with_vars([(rustfs_config::ENV_INTERNODE_IDEMPOTENT_READ_RETRIES, Some("0"))], async {
-            let remote_disk = new_remote_disk_with_transport(Arc::new(RecordingInternodeDataTransport::default())).await;
-            let attempts = Arc::new(std::sync::atomic::AtomicUsize::new(0));
-            let started = time::Instant::now();
-            let channel = TonicEndpoint::from_shared(remote_disk.addr.clone())
-                .expect("remote disk address should parse")
-                .connect_lazy();
-            runtime_sources::cache_test_node_channel(remote_disk.addr.clone(), channel).await;
-
-            let err = remote_disk
-                .execute_read_with_retry(
-                    "read_version",
-                    || {
-                        attempts.fetch_add(1, Ordering::SeqCst);
-                        async {
-                            Err::<(), Error>(DiskError::Io(std_io::Error::new(
-                                std_io::ErrorKind::ConnectionReset,
-                                "connection reset",
-                            )))
-                        }
-                    },
-                    Duration::from_secs(1),
-                )
-                .await
-                .expect_err("zero retries should return the first network error");
-
-            assert!(matches!(err, DiskError::Io(ref io_err) if io_err.kind() == std_io::ErrorKind::ConnectionReset));
-            assert_eq!(attempts.load(Ordering::SeqCst), 1);
-            assert_eq!(started.elapsed(), Duration::ZERO);
-            assert_eq!(remote_disk.runtime_state(), RuntimeDriveHealthState::Suspect);
-            assert!(!runtime_sources::test_node_channel_is_cached(&remote_disk.addr).await);
-            remote_disk.cancel_token.cancel();
-        })
-        .await;
-    }
-
-    #[tokio::test(start_paused = true)]
-    #[serial(remote_disk_read_retry)]
-    async fn execute_read_with_retry_attempt_timeout_marks_health_without_evicting() {
-        let remote_disk = new_remote_disk_with_transport(Arc::new(RecordingInternodeDataTransport::default())).await;
-        let recorder = crate::test_metrics::CapturingRecorder::default();
-        let _recorder_guard = metrics::set_default_local_recorder(&recorder);
-        let attempts = Arc::new(std::sync::atomic::AtomicUsize::new(0));
-        let channel = TonicEndpoint::from_shared(remote_disk.addr.clone())
-            .expect("remote disk address should parse")
-            .connect_lazy();
-        runtime_sources::cache_test_node_channel(remote_disk.addr.clone(), channel).await;
-
-        let err = remote_disk
-            .execute_read_with_retry(
-                "read_version",
-                || {
-                    attempts.fetch_add(1, Ordering::SeqCst);
-                    std::future::pending::<Result<()>>()
-                },
-                Duration::from_millis(100),
-            )
-            .await
-            .expect_err("an in-flight attempt that consumes the deadline should time out");
-
-        assert_eq!(err, DiskError::Timeout);
-        assert_eq!(attempts.load(Ordering::SeqCst), 1);
-        assert_eq!(remote_disk.runtime_state(), RuntimeDriveHealthState::Suspect);
-        assert!(runtime_sources::test_node_channel_is_cached(&remote_disk.addr).await);
-        assert_eq!(
-            recorder.counter_value(
-                "rustfs_drive_op_timeout_total",
-                &[
-                    ("endpoint", remote_disk.endpoint.to_string().as_str()),
-                    ("op", "read_version")
-                ]
-            ),
-            1
-        );
-        remote_disk.cancel_token.cancel();
-    }
-
-    #[tokio::test(start_paused = true)]
-    #[serial(remote_disk_read_retry)]
-    async fn execute_read_with_retry_does_not_retry_business_errors() {
-        let remote_disk = new_remote_disk_with_transport(Arc::new(RecordingInternodeDataTransport::default())).await;
-        let attempts = Arc::new(std::sync::atomic::AtomicUsize::new(0));
-
-        let err = remote_disk
-            .execute_read_with_retry(
-                "read_version",
-                || {
-                    attempts.fetch_add(1, Ordering::SeqCst);
-                    async { Err::<(), Error>(DiskError::FileNotFound) }
-                },
-                Duration::from_secs(1),
-            )
-            .await
-            .expect_err("business errors should be returned directly");
-
-        assert_eq!(err, DiskError::FileNotFound);
-        assert_eq!(attempts.load(Ordering::SeqCst), 1);
-        remote_disk.cancel_token.cancel();
-    }
-
-    #[tokio::test(start_paused = true)]
-    #[serial(remote_disk_read_retry)]
-    async fn execute_read_with_retry_honors_configured_retry_count() {
-        temp_env::async_with_vars([(rustfs_config::ENV_INTERNODE_IDEMPOTENT_READ_RETRIES, Some("2"))], async {
-            let remote_disk = new_remote_disk_with_transport(Arc::new(RecordingInternodeDataTransport::default())).await;
-            let attempts = Arc::new(std::sync::atomic::AtomicUsize::new(0));
-            let started = time::Instant::now();
-            let channel = TonicEndpoint::from_shared(remote_disk.addr.clone())
-                .expect("remote disk address should parse")
-                .connect_lazy();
-            runtime_sources::cache_test_node_channel(remote_disk.addr.clone(), channel).await;
-
-            let err = remote_disk
-                .execute_read_with_retry(
-                    "read_version",
-                    || {
-                        attempts.fetch_add(1, Ordering::SeqCst);
-                        async {
-                            Err::<(), Error>(DiskError::Io(std_io::Error::new(
-                                std_io::ErrorKind::ConnectionReset,
-                                "connection reset",
-                            )))
-                        }
-                    },
-                    Duration::from_secs(1),
-                )
-                .await
-                .expect_err("exhausted retries should return the last network error");
-
-            assert!(matches!(err, DiskError::Io(ref io_err) if io_err.kind() == std_io::ErrorKind::ConnectionReset));
-            assert_eq!(attempts.load(Ordering::SeqCst), 3);
-            assert_eq!(started.elapsed(), Duration::from_millis(150));
-            assert_eq!(remote_disk.runtime_state(), RuntimeDriveHealthState::Suspect);
-            assert!(!runtime_sources::test_node_channel_is_cached(&remote_disk.addr).await);
-            remote_disk.cancel_token.cancel();
-        })
-        .await;
-    }
-
-    #[tokio::test(start_paused = true)]
-    #[serial(remote_disk_read_retry)]
-    async fn execute_read_with_retry_stops_when_disk_turns_offline_during_backoff() {
-        let remote_disk = Arc::new(new_remote_disk_with_transport(Arc::new(RecordingInternodeDataTransport::default())).await);
-        let attempts = Arc::new(std::sync::atomic::AtomicUsize::new(0));
-        let first_attempt = Arc::new(tokio::sync::Notify::new());
-        let task_disk = Arc::clone(&remote_disk);
-        let task_attempts = Arc::clone(&attempts);
-        let task_first_attempt = Arc::clone(&first_attempt);
-
-        let task = tokio::spawn(async move {
-            task_disk
-                .execute_read_with_retry(
-                    "read_version",
-                    move || {
-                        let attempt = task_attempts.fetch_add(1, Ordering::SeqCst);
-                        let first_attempt = Arc::clone(&task_first_attempt);
-                        async move {
-                            if attempt == 0 {
-                                first_attempt.notify_one();
-                                return Err::<(), Error>(DiskError::Io(std_io::Error::new(
-                                    std_io::ErrorKind::ConnectionReset,
-                                    "connection reset",
-                                )));
-                            }
-                            Ok(())
-                        }
-                    },
-                    Duration::from_secs(1),
-                )
-                .await
-        });
-
-        first_attempt.notified().await;
-        tokio::task::yield_now().await;
-        remote_disk
-            .health
-            .force_runtime_state_for_test(RuntimeDriveHealthState::Offline);
-        time::advance(REMOTE_DISK_READ_RETRY_BASE_BACKOFF).await;
-        let err = task
-            .await
-            .expect("retry task should finish")
-            .expect_err("an offline disk must stop before the next attempt");
-
-        assert_eq!(err, DiskError::FaultyDisk);
-        assert_eq!(attempts.load(Ordering::SeqCst), 1);
-        remote_disk.cancel_token.cancel();
-    }
-
    #[tokio::test]
    async fn test_execute_with_timeout_evicts_cached_connection() {
        let addr = "http://127.0.0.1:59991".to_string();
@@ -6152,40 +5603,6 @@ mod tests {
        accept_task.abort();
    }

-    #[tokio::test]
-    async fn read_version_uses_the_metadata_timeout_on_a_stalled_peer() {
-        runtime_sources::ensure_test_rpc_secret();
-        let Some((base_addr, accept_task)) = spawn_stalled_grpc_peer().await else {
-            return;
-        };
-        let remote_disk = remote_disk_for_addr(&base_addr).await;
-
-        temp_env::async_with_vars(
-            [
-                (rustfs_config::ENV_DRIVE_METADATA_TIMEOUT_SECS, Some("1")),
-                (rustfs_config::ENV_DRIVE_MAX_TIMEOUT_DURATION, Some("10")),
-            ],
-            async {
-                let started = time::Instant::now();
-                let err = tokio::time::timeout(
-                    Duration::from_secs(5),
-                    remote_disk.read_version("bucket", "bucket", "object", "", &ReadOptions::default()),
-                )
-                .await
-                .expect("read_version must use the shorter metadata deadline")
-                .expect_err("a stalled peer must fail read_version");
-
-                assert!(matches!(err, DiskError::Timeout), "expected the metadata deadline to fire, got {err:?}");
-                assert!(started.elapsed() >= Duration::from_millis(900));
-                assert!(started.elapsed() < Duration::from_secs(2));
-            },
-        )
-        .await;
-
-        remote_disk.cancel_token.cancel();
-        accept_task.abort();
-    }
-
    #[tokio::test]
    async fn delete_volume_bounds_the_wait_on_a_stalled_peer() {
        runtime_sources::ensure_test_rpc_secret();
@@ -48,6 +48,10 @@ impl RemoteClient {
        Self { addr: endpoint }
    }

+    pub fn from_url(url: url::Url) -> Self {
+        Self { addr: url.to_string() }
+    }
+
    fn build_ping_request() -> PingRequest {
        let mut fbb = flatbuffers::FlatBufferBuilder::new();
        let payload = fbb.create_vector(b"health-check");
@@ -46,6 +46,7 @@ use rustfs_config::{
    SCANNER_SUB_SYS,
 };
 use rustfs_filemeta::FileInfo;
+use rustfs_utils::path::SLASH_SEPARATOR;
 use serde_json::{Map, Value};
 use std::collections::{HashMap, HashSet};
 use std::sync::LazyLock;
@@ -199,6 +200,8 @@ pub const STORAGE_CLASS_SUB_SYS: &str = "storage_class";

 pub const COMMA_SEPARATED_LISTS: &[&str] = &[rustfs_config::oidc::OIDC_SCOPES, rustfs_config::oidc::OIDC_OTHER_AUDIENCES];

+static CONFIG_BUCKET: LazyLock<String> = LazyLock::new(|| format!("{RUSTFS_META_BUCKET}{SLASH_SEPARATOR}{CONFIG_PREFIX}"));
+
 type ServerConfigDecryptFn = crate::bucket::migration::LegacyBlobDecryptFn;

 static SERVER_CONFIG_DECRYPT_FN: LazyLock<RwLock<Option<ServerConfigDecryptFn>>> = LazyLock::new(|| RwLock::new(None));
@@ -13,6 +13,7 @@
 // limitations under the License.

 // #730: configuration migration keeps legacy subsystem definitions available behind this module.
+#![allow(dead_code)]

 mod audit;
 pub mod com;
@@ -101,7 +101,6 @@ const DEFAULT_RRS_STORAGE_CLASS: &str = "EC:1";
 const ZERO_SET_DRIVE_COUNT_ERROR: &str = "set drive count must be greater than zero";

 pub static DEFAULT_INLINE_BLOCK: usize = 128 * 1024;
-const DEFAULT_INLINE_OBJECT_BUDGET: usize = 2 * DEFAULT_INLINE_BLOCK;

 pub static DEFAULT_KVS: LazyLock<KVS> = LazyLock::new(|| {
    let kvs = vec![
@@ -151,8 +150,6 @@ pub struct Config {
    optimize: Option<String>,
    inline_block: usize,
    initialized: bool,
-    #[serde(default, skip_serializing_if = "std::ops::Not::not")]
-    inline_block_explicit: bool,
    #[serde(skip)]
    standard_parities: Vec<PoolParity>,
    #[serde(skip)]
@@ -189,10 +186,6 @@ impl Config {
    /// A topology-bound lookup fails closed for unknown drive counts and for
    /// deserialized legacy configurations that have no pool topology. Legacy
    /// callers retain scalar compatibility through [`Self::get_parity_for_sc`].
-    #[allow(
-        dead_code,
-        reason = "per-set parity resolution asserted by this file's tests (backlog#1823)"
-    )]
    pub(crate) fn parity_for_sc(&self, sc: &str, drives_per_set: usize) -> Option<usize> {
        if !self.initialized {
            return None;
@@ -240,19 +233,17 @@ impl Config {
            .map(|(pool_index, pool)| (pool_index, pool.drives_per_set))
    }

-    pub fn should_inline(&self, shard_size: i64, data_shards: usize, versioned: bool) -> bool {
-        if shard_size < 0 || data_shards == 0 {
+    pub fn should_inline(&self, shard_size: i64, versioned: bool) -> bool {
+        if shard_size < 0 {
            return false;
        }

        let shard_size = shard_size as usize;
-        // Keep the historical two-data-shard object budget while preventing
-        // wider EC layouts from multiplying the maximum inline object size.
-        let inline_block = if self.initialized && self.inline_block_explicit {
-            self.inline_block
-        } else {
-            (DEFAULT_INLINE_OBJECT_BUDGET / data_shards).min(DEFAULT_INLINE_BLOCK)
-        };
+
+        let mut inline_block = DEFAULT_INLINE_BLOCK;
+        if self.initialized {
+            inline_block = self.inline_block;
+        }

        if versioned {
            shard_size <= inline_block / 8
@@ -401,7 +392,6 @@ fn lookup_config_for_pools_with_env(
    }

    let optimize = overrides.optimize;
-    let inline_block_explicit = overrides.inline_block.is_some();
    let inline_block = if let Some(value) = overrides.inline_block {
        let block = value
            .parse::<bytesize::ByteSize>()
@@ -434,7 +424,6 @@ fn lookup_config_for_pools_with_env(
        optimize,
        inline_block,
        initialized: true,
-        inline_block_explicit,
        standard_parities,
        rrs_parities,
    })
@@ -552,26 +541,22 @@ mod tests {
    }

    #[test]
-    fn should_inline_scales_default_threshold_by_data_shards() {
-        let config = lookup_config_for_pools_with_env(&KVS::new(), &[3, 12], no_env_overrides())
-            .expect("default inline policy should resolve for EC2+1 and EC8+4");
+    fn should_inline_preserves_exact_default_shard_boundaries() {
+        let config = Config::default();

-        for (case, shard_size, data_shards, versioned, expected) in [
-            ("EC2+1 unversioned exact", 128 * 1024, 2, false, true),
-            ("EC2+1 unversioned above", 128 * 1024 + 1, 2, false, false),
-            ("EC2+1 versioned exact", 16 * 1024, 2, true, true),
-            ("EC2+1 versioned above", 16 * 1024 + 1, 2, true, false),
-            ("EC8+4 unversioned exact", 32 * 1024, 8, false, true),
-            ("EC8+4 unversioned above", 32 * 1024 + 1, 8, false, false),
-            ("EC8+4 versioned exact", 4 * 1024, 8, true, true),
-            ("EC8+4 versioned above", 4 * 1024 + 1, 8, true, false),
-            ("negative", -1, 2, false, false),
-            ("zero data shards", 0, 0, false, false),
+        for (case, shard_size, versioned, expected) in [
+            ("unversioned below", 128 * 1024 - 1, false, true),
+            ("unversioned exact", 128 * 1024, false, true),
+            ("unversioned above", 128 * 1024 + 1, false, false),
+            ("versioned below", 16 * 1024 - 1, true, true),
+            ("versioned exact", 16 * 1024, true, true),
+            ("versioned above", 16 * 1024 + 1, true, false),
+            ("negative", -1, false, false),
        ] {
            assert_eq!(
-                config.should_inline(shard_size, data_shards, versioned),
+                config.should_inline(shard_size, versioned),
                expected,
-                "{case}: shard_size={shard_size}, data_shards={data_shards}, versioned={versioned}"
+                "{case}: shard_size={shard_size}, versioned={versioned}"
            );
        }
    }
@@ -592,28 +577,13 @@ mod tests {
            let shard_size = erasure.shard_file_size(object_size);
            assert_eq!(shard_size, expected_shard_size, "{case}: object_size={object_size}");
            assert_eq!(
-                config.should_inline(shard_size, erasure.data_shards, versioned),
+                config.should_inline(shard_size, versioned),
                expected,
                "{case}: object_size={object_size}, shard_size={shard_size}, versioned={versioned}"
            );
        }
    }

-    #[test]
-    fn explicit_inline_block_preserves_fixed_per_shard_rollback() {
-        let overrides = StorageClassEnvOverrides {
-            inline_block: Some("128KiB".to_string()),
-            ..Default::default()
-        };
-        let config = lookup_config_for_pools_with_env(&KVS::new(), &[12], overrides)
-            .expect("explicit inline block should resolve for EC8+4");
-
-        assert!(config.should_inline(128 * 1024, 8, false));
-        assert!(!config.should_inline(128 * 1024 + 1, 8, false));
-        assert!(config.should_inline(16 * 1024, 8, true));
-        assert!(!config.should_inline(16 * 1024 + 1, 8, true));
-    }
-
    #[test]
    fn write_capability_contract_only_accepts_implemented_layouts() {
        assert_eq!(SUPPORTED_WRITE_CLASSES, [STANDARD, RRS]);
@@ -807,7 +777,6 @@ mod tests {
        let encoded = serde_json::to_string(&cfg).expect("config should serialize");
        assert!(!encoded.contains("standard_parities"));
        assert!(!encoded.contains("rrs_parities"));
-        assert!(!encoded.contains("inline_block_explicit"));

        let decoded: Config = serde_json::from_str(&encoded).expect("legacy scalar config should deserialize");
        assert_eq!(decoded.get_parity_for_sc(STANDARD), Some(2));
@@ -817,25 +786,6 @@ mod tests {
        assert!(validate_parity(0, 0).is_err());
    }

-    #[test]
-    fn explicit_inline_block_survives_config_round_trip() {
-        let cfg = lookup_config_for_pools_with_env(
-            &KVS::new(),
-            &[12],
-            StorageClassEnvOverrides {
-                inline_block: Some("128KiB".to_string()),
-                ..Default::default()
-            },
-        )
-        .expect("explicit inline block should resolve");
-        assert!(cfg.should_inline(100 * 1024, 8, false));
-
-        let encoded = serde_json::to_string(&cfg).expect("config should serialize");
-        assert!(encoded.contains("\"inline_block_explicit\":true"));
-        let decoded: Config = serde_json::from_str(&encoded).expect("explicit inline config should deserialize");
-        assert!(decoded.should_inline(100 * 1024, 8, false));
-    }
-
    #[test]
    fn lookup_config_reads_rrs_from_class_rrs_key() {
        // Regression: kvs.get(RRS) used RRS="REDUCED_REDUNDANCY" instead of
@@ -13,6 +13,7 @@
 // limitations under the License.

 // #730: pool coordination helpers are being migrated behind runtime owners.
+#![allow(dead_code)]

 pub(crate) mod pools;
 pub(crate) mod sets;
@@ -226,7 +226,6 @@ fn ensure_decommission_start_rebalance_meta_allowed(meta: Option<&RebalanceMeta>
    ensure_decommission_not_rebalancing(meta.is_some_and(is_rebalance_conflicting_with_decommission))
 }

-#[allow(dead_code, reason = "leader precondition asserted by this file's tests (backlog#1823)")]
 fn ensure_local_decommission_pool_leaders(endpoints: &EndpointServerPools, indices: &[usize]) -> Result<()> {
    for idx in indices {
        ensure_local_decommission_pool_leader(endpoints, *idx)?;
@@ -1059,19 +1058,11 @@ fn should_cleanup_decommission_source_entry(decommissioned: usize, total_version
 }

 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
-#[allow(
-    dead_code,
-    reason = "terminal-state classification asserted by this file's tests (backlog#1823)"
-)]
 enum DecommissionTerminalState {
    Completed,
    Failed,
 }

-#[allow(
-    dead_code,
-    reason = "terminal-state classification asserted by this file's tests (backlog#1823)"
-)]
 fn classify_decommission_terminal_state(failed_items_present: bool) -> DecommissionTerminalState {
    if failed_items_present {
        DecommissionTerminalState::Failed
@@ -2275,19 +2266,15 @@ fn decommission_delete_marker_opts(
    version: &rustfs_filemeta::FileInfo,
    version_id: Option<String>,
    src_pool_idx: usize,
-    expected_bucket_incarnation_id: Option<uuid::Uuid>,
 ) -> ObjectOptions {
-    let version_suspended = version.version_id.is_none() && version_id.is_none();
    ObjectOptions {
-        versioned: !version_suspended,
-        version_suspended,
-        version_id: version_id.or_else(|| version_suspended.then(|| uuid::Uuid::nil().to_string())),
+        versioned: true,
+        version_id,
        mod_time: version.mod_time,
        src_pool_idx,
        data_movement: true,
        delete_marker: true,
        skip_decommissioned: true,
-        expected_bucket_incarnation_id,
        delete_replication: version
            .replication_state_internal
            .as_ref()
@@ -2312,7 +2299,6 @@ fn decommission_remote_tiered_opts(
    version: &rustfs_filemeta::FileInfo,
    version_id: Option<String>,
    src_pool_idx: usize,
-    expected_bucket_incarnation_id: Option<uuid::Uuid>,
 ) -> ObjectOptions {
    ObjectOptions {
        versioned: version_id.is_some(),
@@ -2321,9 +2307,6 @@ fn decommission_remote_tiered_opts(
        user_defined: version.metadata.clone(),
        src_pool_idx,
        data_movement: true,
-        include_part_checksums: true,
-        http_preconditions: Some(crate::data_movement::data_movement_target_precondition()),
-        expected_bucket_incarnation_id,
        ..Default::default()
    }
 }
@@ -2822,7 +2805,6 @@ impl ECStore {
        lifecycle_config: Option<BucketLifecycleConfiguration>,
        object_lock_config: Option<ObjectLockConfiguration>,
        replication_config: Option<(ReplicationConfiguration, OffsetDateTime)>,
-        expected_bucket_incarnation_id: Option<uuid::Uuid>,
    ) -> Result<()> {
        debug!(
            event = EVENT_DECOMMISSION_ENTRY,
@@ -2852,11 +2834,6 @@ impl ECStore {
        }
        decommission_cancel_signal_result(rx.is_cancelled())?;

-        let bucket_incarnation_fence = match expected_bucket_incarnation_id {
-            Some(expected) => Some(self.acquire_bucket_incarnation_fence(&bucket, expected).await?),
-            None => None,
-        };
-
        let mut fivs = load_decommission_entry_exact_versions(&set, &entry, &bucket, "file_info_versions").await?;

        fivs.versions
@@ -2917,7 +2894,7 @@ impl ECStore {
                    .delete_object(
                        bucket.as_str(),
                        &version.name,
-                        decommission_delete_marker_opts(version, version_id.clone(), idx, expected_bucket_incarnation_id),
+                        decommission_delete_marker_opts(version, version_id.clone(), idx),
                    )
                    .await
                {
@@ -3007,7 +2984,7 @@ impl ECStore {
                            bucket.as_str(),
                            &version.name,
                            version,
-                            &decommission_remote_tiered_opts(version, version_id.clone(), idx, expected_bucket_incarnation_id),
+                            &decommission_remote_tiered_opts(version, version_id.clone(), idx),
                        )
                        .await
                    {
@@ -3079,11 +3056,7 @@ impl ECStore {
                )
                .await?;

-                if let Err(err) = self
-                    .clone()
-                    .decommission_object(idx, bucket, rd, expected_bucket_incarnation_id)
-                    .await
-                {
+                if let Err(err) = self.clone().decommission_object(idx, bucket, rd).await {
                    if is_decommission_copy_cleanup_safe_error(&err) {
                        ignore = true;
                        cleanup_ignored = true;
@@ -3160,9 +3133,6 @@ impl ECStore {
        }

        if should_cleanup_decommission_source_entry(decommissioned, fivs.versions.len(), expired) {
-            if bucket_incarnation_fence.as_ref().is_some_and(|guard| guard.is_lock_lost()) {
-                return Err(Error::other("decommission bucket incarnation fence was lost before source cleanup"));
-            }
            decommission_cancel_signal_result(rx.is_cancelled())?;

            self.save_decommission_entry_progress_stage(
@@ -3187,12 +3157,6 @@ impl ECStore {
                entry.name.as_str(),
                &fivs,
                &cleanup_preflight_allowed_missing,
-                data_movement::SourceCleanupBucketFence {
-                    expected_incarnation_id: expected_bucket_incarnation_id,
-                    lifecycle_guard: bucket_incarnation_fence
-                        .as_ref()
-                        .and_then(|guard| guard.namespace_lock_guard()),
-                },
                "decommission",
            )
            .await
@@ -3304,11 +3268,6 @@ impl ECStore {
        let mut lifecycle_config = None;
        let mut object_lock_config = None;
        let mut replication_config = None;
-        let expected_bucket_incarnation_id = if bi.name == RUSTFS_META_BUCKET {
-            None
-        } else {
-            Some(self.bucket_incarnation_id_from_disk(&bi.name).await?)
-        };

        if bi.name != RUSTFS_META_BUCKET {
            let _ = resolve_decommission_optional_bucket_config_result(
@@ -3362,7 +3321,6 @@ impl ECStore {
                    let lifecycle_config = lifecycle_config.clone();
                    let object_lock_config = object_lock_config.clone();
                    let replication_config = replication_config.clone();
-                    let expected_bucket_incarnation_id = expected_bucket_incarnation_id;
                    let entry_error = entry_error.clone();
                    let callback_rx = callback_rx.clone();

@@ -3425,7 +3383,6 @@ impl ECStore {
                                lifecycle_config,
                                object_lock_config,
                                replication_config,
-                                expected_bucket_incarnation_id,
                            )
                            .await
                        {
@@ -4211,24 +4168,10 @@ impl ECStore {
    }

    #[tracing::instrument(skip(self, rd))]
-    async fn decommission_object(
-        self: Arc<Self>,
-        pool_idx: usize,
-        bucket: String,
-        rd: GetObjectReader,
-        expected_bucket_incarnation_id: Option<uuid::Uuid>,
-    ) -> Result<()> {
+    async fn decommission_object(self: Arc<Self>, pool_idx: usize, bucket: String, rd: GetObjectReader) -> Result<()> {
        warn!("decommission_object: start {} {}", &bucket, &rd.object_info.name);
        let object_name = rd.object_info.name.clone();
-        let result = data_movement::migrate_object(
-            self,
-            pool_idx,
-            bucket.clone(),
-            rd,
-            expected_bucket_incarnation_id,
-            "decommission_object",
-        )
-        .await;
+        let result = data_movement::migrate_object(self, pool_idx, bucket.clone(), rd, "decommission_object").await;
        if result.is_ok() {
            warn!("decommission_object: migrated {} {}", &bucket, &object_name);
        }
@@ -4404,8 +4347,7 @@ mod tests {
            ..Default::default()
        };

-        let incarnation = uuid::Uuid::new_v4();
-        let opts = decommission_delete_marker_opts(&version, Some("version-id".to_string()), 7, Some(incarnation));
+        let opts = decommission_delete_marker_opts(&version, Some("version-id".to_string()), 7);
        let replication = opts.delete_replication.expect("replication state should be preserved");

        assert!(opts.versioned);
@@ -4415,25 +4357,11 @@ mod tests {
        assert_eq!(opts.src_pool_idx, 7);
        assert_eq!(opts.version_id.as_deref(), Some("version-id"));
        assert_eq!(opts.mod_time, Some(mod_time));
-        assert_eq!(opts.expected_bucket_incarnation_id, Some(incarnation));
        assert_eq!(replication.replica_status, ReplicationStatusType::Replica);
        assert!(replication.delete_marker);
        assert_eq!(replication.replicate_decision_str, "existing");
    }

-    #[test]
-    fn decommission_delete_marker_opts_preserves_suspended_null_version() {
-        let version = rustfs_filemeta::FileInfo {
-            deleted: true,
-            ..Default::default()
-        };
-        let opts = decommission_delete_marker_opts(&version, None, 7, None);
-
-        assert!(!opts.versioned);
-        assert!(opts.version_suspended);
-        assert_eq!(opts.version_id.as_deref(), Some(uuid::Uuid::nil().to_string().as_str()));
-    }
-
    #[test]
    fn test_decommission_object_migration_read_opts_are_raw_data_movement() {
        let opts = decommission_object_migration_read_opts(Some("vid-1".to_string()));
@@ -4455,8 +4383,7 @@ mod tests {
            ..Default::default()
        };

-        let incarnation = uuid::Uuid::new_v4();
-        let opts = decommission_remote_tiered_opts(&version, Some("version-id".to_string()), 9, Some(incarnation));
+        let opts = decommission_remote_tiered_opts(&version, Some("version-id".to_string()), 9);

        assert!(opts.versioned);
        assert!(opts.data_movement);
@@ -4464,9 +4391,6 @@ mod tests {
        assert_eq!(opts.version_id.as_deref(), Some("version-id"));
        assert_eq!(opts.mod_time, Some(mod_time));
        assert_eq!(opts.user_defined.get("x-amz-meta-key").map(String::as_str), Some("value"));
-        assert!(opts.include_part_checksums);
-        assert!(opts.http_preconditions.is_some());
-        assert_eq!(opts.expected_bucket_incarnation_id, Some(incarnation));
    }

    #[test]
@@ -12,16 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.

-//! Per-disk usage snapshots persisted under the metadata bucket.
-//!
-//! **Nothing calls into this module.** It landed complete with tests in #5307
-//! (2026-07-27) and its aggregation entry point,
-//! [`crate::data_usage::aggregate_local_snapshots`], has never had a caller in
-//! the tree's history. The live data-usage path is
-//! `load_data_usage_from_backend` / `store_data_usage_in_backend`. The items
-//! below therefore carry individual `dead_code` allows rather than a module
-//! blanket, so the gap stays greppable until it is either wired up or removed.
-
 use crate::data_usage::BucketUsageInfo;
 use crate::disk::RUSTFS_META_BUCKET;
 use crate::error::{Error, Result};
@@ -36,12 +26,10 @@ pub const DATA_USAGE_DIR: &str = "datausage";
 /// Directory used to store incremental scan state files under the metadata bucket.
 pub const DATA_USAGE_STATE_DIR: &str = "datausage/state";
 /// Snapshot file format version, allows forward compatibility if the structure evolves.
-#[allow(dead_code, reason = "unwired local usage-snapshot feature; see module docs (backlog#1823)")]
 pub const LOCAL_USAGE_SNAPSHOT_VERSION: u32 = 1;

 /// Additional metadata describing which disk produced the snapshot.
 #[derive(Debug, Clone, Serialize, Deserialize, Default)]
-#[allow(dead_code, reason = "unwired local usage-snapshot feature; see module docs (backlog#1823)")]
 pub struct LocalUsageSnapshotMeta {
    /// Disk UUID stored as a string for simpler serialization.
    pub disk_id: String,
@@ -55,7 +43,6 @@ pub struct LocalUsageSnapshotMeta {

 /// Usage snapshot produced by a single disk.
 #[derive(Debug, Clone, Serialize, Deserialize, Default)]
-#[allow(dead_code, reason = "unwired local usage-snapshot feature; see module docs (backlog#1823)")]
 pub struct LocalUsageSnapshot {
    /// Format version recorded in the snapshot.
    pub format_version: u32,
@@ -77,7 +64,6 @@ pub struct LocalUsageSnapshot {
    pub objects_total_size: u64,
 }

-#[allow(dead_code, reason = "unwired local usage-snapshot feature; see module docs (backlog#1823)")]
 impl LocalUsageSnapshot {
    /// Create an empty snapshot with the default format version filled in.
    pub fn new(meta: LocalUsageSnapshotMeta) -> Self {
@@ -113,13 +99,11 @@ impl LocalUsageSnapshot {
 }

 /// Build the snapshot file name `<disk-id>.json`.
-#[allow(dead_code, reason = "unwired local usage-snapshot feature; see module docs (backlog#1823)")]
 pub fn snapshot_file_name(disk_id: &str) -> String {
    format!("{disk_id}.json")
 }

 /// Build the object path relative to `RUSTFS_META_BUCKET`, e.g. `datausage/<disk-id>.json`.
-#[allow(dead_code, reason = "unwired local usage-snapshot feature; see module docs (backlog#1823)")]
 pub fn snapshot_object_path(disk_id: &str) -> String {
    format!("{}/{}", DATA_USAGE_DIR, snapshot_file_name(disk_id))
 }
@@ -135,13 +119,11 @@ pub fn data_usage_state_dir(root: &Path) -> PathBuf {
 }

 /// Build the absolute path to the snapshot file for the provided disk ID.
-#[allow(dead_code, reason = "unwired local usage-snapshot feature; see module docs (backlog#1823)")]
 pub fn snapshot_path(root: &Path, disk_id: &str) -> PathBuf {
    data_usage_dir(root).join(snapshot_file_name(disk_id))
 }

 /// Read a snapshot from disk if it exists.
-#[allow(dead_code, reason = "unwired local usage-snapshot feature; see module docs (backlog#1823)")]
 pub async fn read_snapshot(root: &Path, disk_id: &str) -> Result<Option<LocalUsageSnapshot>> {
    let path = snapshot_path(root, disk_id);
    match fs::read(&path).await {
@@ -156,7 +138,6 @@ pub async fn read_snapshot(root: &Path, disk_id: &str) -> Result<Option<LocalUsa
 }

 /// Persist a snapshot to disk, creating directories as needed and overwriting any existing file.
-#[allow(dead_code, reason = "unwired local usage-snapshot feature; see module docs (backlog#1823)")]
 pub async fn write_snapshot(root: &Path, disk_id: &str, snapshot: &LocalUsageSnapshot) -> Result<()> {
    let dir = data_usage_dir(root);
    fs::create_dir_all(&dir).await.map_err(Error::other)?;
@@ -13,6 +13,7 @@
 // limitations under the License.

 // #730: scanner/data-usage state is partially migrated and still owns staged cache helpers.
+#![allow(dead_code)]

 pub mod local_snapshot;

@@ -33,8 +34,8 @@ use crate::{
 pub use local_snapshot::{LocalUsageSnapshot, read_snapshot as read_local_snapshot, snapshot_path};
 use rustfs_data_usage::{
    BucketTargetUsageInfo, BucketUsageInfo, CompressionTotalInfo, DATA_USAGE_OBJECT_NAME, DATA_USAGE_OBSERVED_OBJECT_NAME,
-    DataUsageCache, DataUsageInfo, DiskUsageStatus, LEGACY_DATA_USAGE_OBJECT_NAME, SizeHistogram, VersionsHistogram,
-    observed_data_usage_is_newer,
+    DataUsageCache, DataUsageEntry, DataUsageInfo, DiskUsageStatus, LEGACY_DATA_USAGE_OBJECT_NAME, SizeHistogram, SizeSummary,
+    VersionsHistogram, observed_data_usage_is_newer,
 };
 use rustfs_io_metrics::record_system_path_failure;
 use rustfs_utils::path::SLASH_SEPARATOR;
@@ -54,6 +55,7 @@ use tracing::{debug, error, info, instrument};
 // Data usage storage constants
 pub const DATA_USAGE_ROOT: &str = SLASH_SEPARATOR;
 const DATA_COMPRESSION_TOTAL_NAME: &str = ".compression.json";
+const DATA_USAGE_BLOOM_NAME: &str = ".bloomcycle.bin";
 pub const DATA_USAGE_CACHE_NAME: &str = ".usage-cache.bin";
 const DATA_USAGE_CACHE_TTL_SECS: u64 = 30;
 const LIVE_BUCKET_USAGE_MAX_ENTRIES: u64 = 1024;
@@ -311,6 +313,11 @@ lazy_static::lazy_static! {
        LEGACY_DATA_USAGE_OBJECT_NAME
    );
    static ref LEGACY_DATA_USAGE_OBJ_BACKUP_PATH: String = format!("{}.bkp", LEGACY_DATA_USAGE_OBJ_NAME_PATH.as_str());
+    pub static ref DATA_USAGE_BLOOM_NAME_PATH: String = format!("{}{}{}",
+        crate::disk::BUCKET_META_PREFIX,
+        SLASH_SEPARATOR,
+        DATA_USAGE_BLOOM_NAME
+    );
    pub static ref DATA_COMPRESSION_TOTAL_NAME_PATH: String = format!("{}{}{}",
        crate::disk::BUCKET_META_PREFIX,
        SLASH_SEPARATOR,
@@ -851,10 +858,6 @@ async fn resolve_loaded_snapshot_pair_with_source(
    }
 }

-#[allow(
-    dead_code,
-    reason = "primary/backup snapshot fallback asserted by this file's tests (backlog#1823)"
-)]
 async fn resolve_loaded_snapshot(
    primary: Result<Vec<u8>, Error>,
    backup: impl Future<Output = Result<Vec<u8>, Error>>,
@@ -1184,10 +1187,6 @@ pub async fn invalidate_admin_data_usage_snapshot_cache() {
 }

 /// Aggregate usage information from local disk snapshots.
-#[allow(
-    dead_code,
-    reason = "reached only through aggregate_local_snapshots, which has no caller (backlog#1823)"
-)]
 fn merge_snapshot(aggregated: &mut DataUsageInfo, mut snapshot: LocalUsageSnapshot, latest_update: &mut Option<SystemTime>) {
    if let Some(update) = snapshot.last_update
        && latest_update.is_none_or(|current| update > current)
@@ -1221,10 +1220,6 @@ fn merge_snapshot(aggregated: &mut DataUsageInfo, mut snapshot: LocalUsageSnapsh
    }
 }

-#[allow(
-    dead_code,
-    reason = "entry point of the local usage-snapshot feature, which has had no caller since it landed in #5307 (backlog#1823)"
-)]
 pub async fn aggregate_local_snapshots(store: Arc<ECStore>) -> Result<(Vec<DiskUsageStatus>, DataUsageInfo), Error> {
    let mut aggregated = DataUsageInfo::default();
    let mut latest_update: Option<SystemTime> = None;
@@ -1360,7 +1355,7 @@ impl BucketUsageAccumulator {
            return Ok(());
        }

-        let object_size = quota_object_size(object)?;
+        let object_size = object.size.max(0) as u64;
        self.current_live_versions = self.current_live_versions.saturating_add(1);
        self.size_histogram.add(object_size);
        self.total_size = self.total_size.saturating_add(object_size);
@@ -1390,31 +1385,6 @@ impl BucketUsageAccumulator {
    }
 }

-pub fn quota_object_size(object: &ObjectInfo) -> Result<u64, Error> {
-    let logical_size = u64::try_from(object.get_actual_size().map_err(Error::other)?).map_err(|_| Error::PartMissingOrCorrupt)?;
-    let persisted_part_size = if object.parts.is_empty() {
-        u64::try_from(object.size).map_err(|_| Error::PartMissingOrCorrupt)?
-    } else {
-        object.parts.iter().try_fold(0_u64, |total, part| {
-            // Compressed streaming objects persist -1 when the transformed
-            // part size is unknown. The physical part size remains a valid
-            // quota floor; reject only non-negative values that overflow.
-            let actual_size = if part.actual_size < 0 {
-                if object.is_compressed() {
-                    0
-                } else {
-                    return Err(Error::PartMissingOrCorrupt);
-                }
-            } else {
-                u64::try_from(part.actual_size).map_err(|_| Error::PartMissingOrCorrupt)?
-            };
-            let part_size = actual_size.max(u64::try_from(part.size).map_err(|_| Error::PartMissingOrCorrupt)?);
-            total.checked_add(part_size).ok_or(Error::PartMissingOrCorrupt)
-        })?
-    };
-    Ok(logical_size.max(persisted_part_size))
-}
-
 type UsageVersionPage = StorageListObjectVersionsInfo<ObjectInfo>;

 pub async fn compute_bucket_usage(store: Arc<ECStore>, bucket_name: &str) -> Result<BucketUsageInfo, Error> {
@@ -1772,6 +1742,11 @@ pub async fn record_bucket_object_write_unknown_previous_memory(bucket: &str, ne
    entry.pending_scanner_position = None;
 }

+/// Fast in-memory increment for immediate quota consistency.
+pub async fn increment_bucket_usage_memory(bucket: &str, size_increment: u64) {
+    record_bucket_object_write_memory(bucket, None, size_increment).await;
+}
+
 /// Fast in-memory update for successful object deletes.
 pub async fn record_bucket_object_delete_memory(bucket: &str, deleted_size: u64, removed_current_object: bool) {
    ensure_bucket_usage_cached(bucket).await;
@@ -1814,6 +1789,11 @@ pub async fn record_bucket_delete_marker_memory(bucket: &str) {
    entry.pending_scanner_position = None;
 }

+/// Fast in-memory decrement for immediate quota consistency
+pub async fn decrement_bucket_usage_memory(bucket: &str, size_decrement: u64) {
+    record_bucket_object_delete_memory(bucket, size_decrement, size_decrement > 0).await;
+}
+
 /// Get bucket usage from the authoritative cache for this topology.
 async fn get_persisted_bucket_usage(bucket: &str) -> Option<u64> {
    let store = runtime_sources::object_store_handle()?;
@@ -2008,6 +1988,91 @@ pub async fn apply_bucket_usage_memory_overlay(data_usage_info: &mut DataUsageIn
    apply_bucket_usage_memory_overlay_if_authoritative(data_usage_info, authoritative).await;
 }

+/// Sync memory cache with backend data (called by scanner)
+pub async fn sync_memory_cache_with_backend() -> Result<(), Error> {
+    if let Some(store) = runtime_sources::object_store_handle() {
+        match load_data_usage_from_backend(store.clone()).await {
+            Ok(data_usage_info) => {
+                replace_bucket_usage_memory_from_info(&data_usage_info).await;
+            }
+            Err(e) => {
+                debug!("Failed to sync memory cache with backend: {}", e);
+            }
+        }
+    }
+    Ok(())
+}
+
+/// Create a data usage cache entry from size summary
+pub fn create_cache_entry_from_summary(summary: &SizeSummary) -> DataUsageEntry {
+    let mut entry = DataUsageEntry::default();
+    entry.add_sizes(summary);
+    entry
+}
+
+/// Convert data usage cache to DataUsageInfo
+pub fn cache_to_data_usage_info(
+    cache: &DataUsageCache,
+    path: &str,
+    buckets: &[crate::storage_api_contracts::bucket::BucketInfo],
+) -> DataUsageInfo {
+    let e = match cache.find(path) {
+        Some(e) => e,
+        None => return DataUsageInfo::default(),
+    };
+    let flat = cache.flatten(&e);
+
+    let mut buckets_usage = HashMap::new();
+    for bucket in buckets.iter() {
+        let e = match cache.find(&bucket.name) {
+            Some(e) => e,
+            None => continue,
+        };
+        let flat = cache.flatten(&e);
+        let mut bui = BucketUsageInfo {
+            size: flat.size as u64,
+            versions_count: flat.versions as u64,
+            objects_count: flat.objects as u64,
+            delete_markers_count: flat.delete_markers as u64,
+            object_size_histogram: flat.obj_sizes.to_map(),
+            object_versions_histogram: flat.obj_versions.to_map(),
+            ..Default::default()
+        };
+
+        if let Some(rs) = &flat.replication_stats {
+            bui.replica_size = rs.replica_size;
+            bui.replica_count = rs.replica_count;
+
+            for (arn, stat) in rs.targets.iter() {
+                bui.replication_info.insert(
+                    arn.clone(),
+                    BucketTargetUsageInfo {
+                        replication_pending_size: stat.pending_size,
+                        replicated_size: stat.replicated_size,
+                        replication_failed_size: stat.failed_size,
+                        replication_pending_count: stat.pending_count,
+                        replication_failed_count: stat.failed_count,
+                        replicated_count: stat.replicated_count,
+                        ..Default::default()
+                    },
+                );
+            }
+        }
+        buckets_usage.insert(bucket.name.clone(), bui);
+    }
+
+    DataUsageInfo {
+        last_update: cache.info.last_update,
+        objects_total_count: flat.objects as u64,
+        versions_total_count: flat.versions as u64,
+        delete_markers_total_count: flat.delete_markers as u64,
+        objects_total_size: flat.size as u64,
+        buckets_count: e.children.len() as u64,
+        buckets_usage,
+        ..Default::default()
+    }
+}
+
 // Helper functions for DataUsageCache operations
 pub async fn load_data_usage_cache(store: &crate::set_disk::SetDisks, name: &str) -> crate::error::Result<DataUsageCache> {
    use crate::disk::{BUCKET_META_PREFIX, RUSTFS_META_BUCKET};
@@ -3059,102 +3124,6 @@ mod tests {
        assert_eq!(usage.object_versions_histogram.get("BETWEEN_1000_AND_10000"), Some(&1));
    }

-    #[test]
-    fn bucket_usage_uses_the_larger_of_logical_and_physical_size() {
-        let mut metadata = HashMap::new();
-        rustfs_utils::http::insert_str(
-            &mut metadata,
-            rustfs_utils::http::SUFFIX_COMPRESSION,
-            "klauspost/compress/s2".to_string(),
-        );
-        rustfs_utils::http::insert_str(&mut metadata, rustfs_utils::http::SUFFIX_ACTUAL_SIZE, "4096".to_string());
-        let object = ObjectInfo {
-            name: "compressed".to_string(),
-            size: 128,
-            user_defined: Arc::new(metadata),
-            ..Default::default()
-        };
-        let mut usage = BucketUsageAccumulator::default();
-        usage
-            .record("bucket", &object)
-            .expect("valid compressed metadata should be counted");
-        assert_eq!(usage.finish().size, 4096);
-
-        let mut framed_metadata = HashMap::new();
-        rustfs_utils::http::insert_str(
-            &mut framed_metadata,
-            rustfs_utils::http::SUFFIX_COMPRESSION,
-            "klauspost/compress/s2".to_string(),
-        );
-        rustfs_utils::http::insert_str(&mut framed_metadata, rustfs_utils::http::SUFFIX_ACTUAL_SIZE, "1".to_string());
-        let framed = ObjectInfo {
-            name: "framed".to_string(),
-            size: 17,
-            user_defined: Arc::new(framed_metadata),
-            ..Default::default()
-        };
-        assert_eq!(quota_object_size(&framed).expect("physical framing must remain quota-accounted"), 17);
-
-        let legacy_compressed_part = ObjectInfo {
-            name: "legacy-compressed-part".to_string(),
-            size: 1,
-            user_defined: Arc::new((*framed.user_defined).clone()),
-            parts: Arc::new(vec![rustfs_filemeta::ObjectPartInfo {
-                size: 1,
-                actual_size: -1,
-                ..Default::default()
-            }]),
-            ..Default::default()
-        };
-        assert_eq!(
-            quota_object_size(&legacy_compressed_part).expect("unknown compressed part size is a valid sentinel"),
-            1
-        );
-
-        let uncompressed_negative_part = ObjectInfo {
-            name: "uncompressed-negative-part".to_string(),
-            size: 1,
-            parts: Arc::new(vec![rustfs_filemeta::ObjectPartInfo {
-                size: 1,
-                actual_size: -1,
-                ..Default::default()
-            }]),
-            ..Default::default()
-        };
-        assert!(matches!(quota_object_size(&uncompressed_negative_part), Err(Error::PartMissingOrCorrupt)));
-
-        let mut corrupt_metadata = (*object.user_defined).clone();
-        rustfs_utils::http::insert_str(&mut corrupt_metadata, rustfs_utils::http::SUFFIX_ACTUAL_SIZE, "-1".to_string());
-        let corrupt = ObjectInfo {
-            user_defined: Arc::new(corrupt_metadata),
-            ..object
-        };
-        assert!(matches!(quota_object_size(&corrupt), Err(Error::PartMissingOrCorrupt)));
-
-        let mut poisoned_metadata = HashMap::new();
-        rustfs_utils::http::insert_str(
-            &mut poisoned_metadata,
-            rustfs_utils::http::SUFFIX_COMPRESSION,
-            "klauspost/compress/s2".to_string(),
-        );
-        rustfs_utils::http::insert_str(&mut poisoned_metadata, rustfs_utils::http::SUFFIX_ACTUAL_SIZE, "1".to_string());
-        let poisoned = ObjectInfo {
-            name: "legacy-swift-metadata".to_string(),
-            size: 4096,
-            user_defined: Arc::new(poisoned_metadata),
-            parts: Arc::new(vec![rustfs_filemeta::ObjectPartInfo {
-                size: 4096,
-                actual_size: 4096,
-                ..Default::default()
-            }]),
-            ..Default::default()
-        };
-        assert_eq!(
-            quota_object_size(&poisoned).expect("persisted part accounting must bound legacy user metadata"),
-            4096
-        );
-    }
-
    #[tokio::test]
    #[serial]
    async fn live_bucket_usage_refreshes_are_coalesced_only_while_in_flight() {
@@ -653,7 +653,6 @@ fn reconcile_servers_with_endpoint_topology(
    (added, report)
 }

-#[allow(dead_code, reason = "exercised by this file's topology tests (backlog#1823)")]
 fn server_topology_completeness_report(
    servers: &[ServerProperties],
    endpoints: &EndpointServerPools,
@@ -46,49 +46,21 @@ pub(crate) const GET_CODEC_STREAMING_OBJECT_CLASS_MULTIPART: &str = "multipart";
 pub(crate) const GET_STAGE_DECODE: &str = "decode";
 pub(crate) const GET_STAGE_EMIT: &str = "emit";
 pub(crate) const GET_STAGE_FILL: &str = "fill";
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const GET_STAGE_FIRST_BYTE: &str = "first_byte";
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const GET_STAGE_FIRST_METADATA_RESPONSE: &str = "first_metadata_response";
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const GET_STAGE_FIRST_VALID_METADATA_RESPONSE: &str = "first_valid_metadata_response";
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const GET_STAGE_FIRST_SHARD_READ: &str = "first_shard_read";
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const GET_STAGE_FULL_BODY: &str = "full_body";
 pub(crate) const GET_STAGE_INLINE_PREPARE: &str = "inline_prepare";
 pub(crate) const GET_STAGE_LOCK_ACQUIRE: &str = "lock_acquire";
 pub(crate) const GET_STAGE_METADATA: &str = "metadata";
 pub(crate) const GET_STAGE_METADATA_CACHE_LOOKUP: &str = "metadata_cache_lookup";
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const GET_STAGE_METADATA_FANOUT: &str = "metadata_fanout";
 pub(crate) const GET_STAGE_METADATA_RESOLVE: &str = "metadata_resolve";
 pub(crate) const GET_STAGE_OBJECT_INFO: &str = "object_info";
 pub(crate) const GET_STAGE_OUTPUT_LOCK_WAIT: &str = "output_lock_wait";
 pub(crate) const GET_STAGE_OUTPUT_POLL: &str = "output_poll";
 pub(crate) const GET_STAGE_PATH_DECISION: &str = "path_decision";
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const GET_STAGE_QUORUM_REACHED: &str = "quorum_reached";
 pub(crate) const GET_STAGE_RANGE: &str = "range";
 pub(crate) const GET_STAGE_READER_SETUP: &str = "reader_setup";
@@ -112,28 +84,12 @@ pub(crate) const GET_STAGE_READER_STREAM_FIRST_READ: &str = "reader_stream_first
 pub(crate) const GET_STAGE_READER_TASK_BITROT_READER_INIT: &str = "reader_task_bitrot_reader_init";
 pub(crate) const GET_STAGE_READER_TASK_FILE_OPEN: &str = "reader_task_file_open";
 pub(crate) const GET_STAGE_READER_TASK_READER_CONSTRUCTION: &str = "reader_task_reader_construction";
-pub(crate) const GET_STAGE_READ_VERSION_DECODE: &str = "read_version_decode";
-pub(crate) const GET_STAGE_READ_VERSION_PATH_CHECK: &str = "read_version_path_check";
-pub(crate) const GET_STAGE_READ_VERSION_PATH_RESOLVE: &str = "read_version_path_resolve";
-pub(crate) const GET_STAGE_READ_VERSION_XLMETA_READ: &str = "read_version_xlmeta_read";
 pub(crate) const GET_STAGE_RECONSTRUCT: &str = "reconstruct";
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const GET_STAGE_RESPONSE_HANDOFF: &str = "response_handoff";
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const GET_STAGE_SLOWEST_METADATA_RESPONSE: &str = "slowest_metadata_response";
 pub(crate) const GET_STAGE_STRIPE_READ: &str = "stripe_read";
 pub(crate) const GET_STAGE_STRIPE_READ_FIRST_SHARD: &str = "stripe_read_first_shard";
 pub(crate) const GET_STAGE_STRIPE_READ_QUORUM: &str = "stripe_read_quorum";
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const GET_STAGE_BITROT_VERIFY: &str = "bitrot_verify";

 pub(crate) const GET_READER_BUFFER_OUTPUT: &str = "output";
@@ -181,7 +137,6 @@ pub(crate) const GET_METADATA_CACHE_REASON_NO_LOCK: &str = "no_lock";
 pub(crate) const GET_METADATA_CACHE_REASON_NOT_FOUND_OR_EXPIRED: &str = "not_found_or_expired";
 pub(crate) const GET_METADATA_CACHE_REASON_NOT_READ_DATA: &str = "not_read_data";
 pub(crate) const GET_METADATA_CACHE_REASON_PART_NUMBER: &str = "part_number";
-pub(crate) const GET_METADATA_CACHE_REASON_PART_CHECKSUMS: &str = "part_checksums";
 pub(crate) const GET_METADATA_CACHE_REASON_RAW_DATA_MOVEMENT_READ: &str = "raw_data_movement_read";
 pub(crate) const GET_METADATA_CACHE_REASON_STALE_PUBLICATION: &str = "stale_publication";
 pub(crate) const GET_METADATA_CACHE_REASON_USABLE: &str = "usable";
@@ -199,20 +154,8 @@ pub(crate) const GET_METADATA_EARLY_STOP_REASON_VERSION_NOT_FOUND: &str = "versi
 pub(crate) const GET_METADATA_EARLY_STOP_REASON_VERSION_MATCH_QUORUM: &str = "version_match_quorum";

 /// Early-stop active state labels
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const EARLY_STOP_ACTIVE_HIT: &str = "hit";
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const EARLY_STOP_ACTIVE_MISS: &str = "miss";
-#[allow(
-    dead_code,
-    reason = "GET stage vocabulary; value pinned by this file's tests, no writer yet (backlog#1823)"
-)]
 pub(crate) const EARLY_STOP_ACTIVE_DISABLED: &str = "disabled";

 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
@@ -498,10 +441,6 @@ mod tests {
        assert_eq!(GET_STAGE_QUORUM_REACHED, "quorum_reached");
        assert_eq!(GET_STAGE_RANGE, "range");
        assert_eq!(GET_STAGE_READER_SETUP, "reader_setup");
-        assert_eq!(GET_STAGE_READ_VERSION_DECODE, "read_version_decode");
-        assert_eq!(GET_STAGE_READ_VERSION_PATH_CHECK, "read_version_path_check");
-        assert_eq!(GET_STAGE_READ_VERSION_PATH_RESOLVE, "read_version_path_resolve");
-        assert_eq!(GET_STAGE_READ_VERSION_XLMETA_READ, "read_version_xlmeta_read");
        assert_eq!(GET_STAGE_RECONSTRUCT, "reconstruct");
        assert_eq!(GET_STAGE_RESPONSE_HANDOFF, "response_handoff");
        assert_eq!(GET_STAGE_SLOWEST_METADATA_RESPONSE, "slowest_metadata_response");
@@ -541,7 +480,6 @@ mod tests {
        assert_eq!(GET_METADATA_CACHE_REASON_NO_LOCK, "no_lock");
        assert_eq!(GET_METADATA_CACHE_REASON_NOT_FOUND_OR_EXPIRED, "not_found_or_expired");
        assert_eq!(GET_METADATA_CACHE_REASON_NOT_READ_DATA, "not_read_data");
-        assert_eq!(GET_METADATA_CACHE_REASON_PART_CHECKSUMS, "part_checksums");
        assert_eq!(GET_METADATA_CACHE_REASON_PART_NUMBER, "part_number");
        assert_eq!(GET_METADATA_CACHE_REASON_RAW_DATA_MOVEMENT_READ, "raw_data_movement_read");
        assert_eq!(GET_METADATA_CACHE_REASON_STALE_PUBLICATION, "stale_publication");
@@ -13,6 +13,8 @@
 // limitations under the License.

 // #730: diagnostics constants are staged for request-path telemetry migration.
+#![allow(dead_code)]

 pub(crate) mod admin_server_info;
 pub(crate) mod get;
+pub(crate) mod pool;
@@ -0,0 +1,30 @@
+// Copyright 2024 RustFS Team
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! BytesPool metric label constants.
+//!
+//! These constants are used when recording pool acquisition and return
+//! metrics to avoid string allocations and ensure label consistency.
+
+/// BytesPool tier labels
+pub const POOL_TIER_SMALL: &str = "small";
+pub const POOL_TIER_MEDIUM: &str = "medium";
+pub const POOL_TIER_LARGE: &str = "large";
+pub const POOL_TIER_XLARGE: &str = "xlarge";
+
+/// BytesPool outcome labels
+pub const POOL_OUTCOME_HIT: &str = "hit";
+pub const POOL_OUTCOME_MISS: &str = "miss";
+pub const POOL_OUTCOME_RECYCLED: &str = "recycled";
+pub const POOL_OUTCOME_DROPPED: &str = "dropped";
@@ -241,40 +241,6 @@ pub fn get_drive_list_dir_timeout() -> Duration {
    )
 }

-pub(crate) trait DiskStoreRenameDataExt {
-    async fn rename_data_borrowed(
-        &self,
-        src_volume: &str,
-        src_path: &str,
-        fi: &FileInfo,
-        dst_volume: &str,
-        dst_path: &str,
-    ) -> Result<RenameDataResp>;
-}
-
-impl DiskStoreRenameDataExt for LocalDiskWrapper {
-    async fn rename_data_borrowed(
-        &self,
-        src_volume: &str,
-        src_path: &str,
-        fi: &FileInfo,
-        dst_volume: &str,
-        dst_path: &str,
-    ) -> Result<RenameDataResp> {
-        self.track_disk_health_mutation(
-            "rename_data",
-            DiskMetricMutation::Write,
-            || async {
-                self.disk
-                    .rename_data_borrowed(src_volume, src_path, fi, dst_volume, dst_path)
-                    .await
-            },
-            get_max_timeout_duration(),
-        )
-        .await
-    }
-}
-
 pub fn get_drive_walkdir_timeout() -> Duration {
    get_drive_timeout_duration(
        rustfs_config::ENV_DRIVE_WALKDIR_TIMEOUT_SECS,
@@ -2019,8 +1985,13 @@ impl DiskAPI for LocalDiskWrapper {
        dst_volume: &str,
        dst_path: &str,
    ) -> Result<RenameDataResp> {
-        self.rename_data_borrowed(src_volume, src_path, &fi, dst_volume, dst_path)
-            .await
+        self.track_disk_health_mutation(
+            "rename_data",
+            DiskMetricMutation::Write,
+            || async { self.disk.rename_data(src_volume, src_path, fi, dst_volume, dst_path).await },
+            get_max_timeout_duration(),
+        )
+        .await
    }

    async fn list_dir(&self, origvolume: &str, volume: &str, dir_path: &str, count: i32) -> Result<Vec<String>> {
@@ -2051,21 +2022,6 @@ impl DiskAPI for LocalDiskWrapper {
        .await
    }

-    async fn read_file_stream_chunks(
-        &self,
-        volume: &str,
-        path: &str,
-        offset: usize,
-        length: usize,
-    ) -> Result<Option<rustfs_rio::ChunkReaderBox>> {
-        self.track_disk_health_with_op(
-            "read_file_stream_chunks",
-            || async { self.disk.read_file_stream_chunks(volume, path, offset, length).await },
-            get_max_timeout_duration(),
-        )
-        .await
-    }
-
    async fn read_file_mmap_copy(&self, volume: &str, path: &str, offset: usize, length: usize) -> Result<bytes::Bytes> {
        self.track_disk_health_with_op(
            "read_file_mmap_copy",
@@ -15,11 +15,6 @@
 use crate::config::storageclass::DEFAULT_INLINE_BLOCK;
 use crate::crash_inject::{self, CrashPoint};
 use crate::data_usage::local_snapshot::ensure_data_usage_layout;
-use crate::diagnostics::get::{
-    GET_OBJECT_PATH_INTERNAL_META, GET_OBJECT_PATH_LEGACY_DUPLEX, GET_STAGE_READ_VERSION_DECODE,
-    GET_STAGE_READ_VERSION_PATH_CHECK, GET_STAGE_READ_VERSION_PATH_RESOLVE, GET_STAGE_READ_VERSION_XLMETA_READ,
-    get_stage_timer_if_enabled, record_get_stage_duration_if_enabled,
-};
 #[cfg(test)]
 use crate::disk::HEALING_MARKER_PATH;
 use crate::disk::disk_store::{get_drive_walkdir_stall_timeout, get_object_disk_read_timeout};
@@ -27,18 +22,17 @@ use crate::disk::{
    BUCKET_META_PREFIX, CHECK_PART_FILE_CORRUPT, CHECK_PART_FILE_NOT_FOUND, CHECK_PART_SUCCESS, CHECK_PART_UNKNOWN,
    CHECK_PART_VOLUME_NOT_FOUND, CheckPartsResp, ConditionalFileUpdate, DataDirDeleteStatus, DeleteOptions, DiskAPI, DiskInfo,
    DiskInfoOptions, DiskLocation, DiskMetrics, FileInfoVersions, FileReader, FileWriter, MmapCopyStageMetrics, OldCurrentSize,
-    PART_TRANSACTION_NEW_META, PART_TRANSACTION_OLD_META, PART_TRANSACTION_ROLLBACK, PartTransactionAction,
-    QUOTA_MUTATION_FENCE_METADATA_SUFFIX, RUSTFS_META_BUCKET, RUSTFS_META_TMP_BUCKET, RUSTFS_META_TMP_DELETED_BUCKET,
-    ReadMultipleReq, ReadMultipleResp, ReadOptions, RenameDataResp, STORAGE_FORMAT_FILE, STORAGE_FORMAT_FILE_BACKUP,
-    SnapshotLeaseToken, UpdateMetadataOpts, VolumeInfo, WalkDirOptions, conv_part_err_to_int,
+    PART_TRANSACTION_NEW_META, PART_TRANSACTION_OLD_META, PART_TRANSACTION_ROLLBACK, PartTransactionAction, RUSTFS_META_BUCKET,
+    RUSTFS_META_TMP_BUCKET, RUSTFS_META_TMP_DELETED_BUCKET, ReadMultipleReq, ReadMultipleResp, ReadOptions, RenameDataResp,
+    STORAGE_FORMAT_FILE, STORAGE_FORMAT_FILE_BACKUP, SnapshotLeaseToken, UpdateMetadataOpts, VolumeInfo, WalkDirOptions,
+    conv_part_err_to_int,
    endpoint::Endpoint,
    error::{DiskError, Error, FileAccessDeniedWithContext, Result},
    error_conv::{to_access_error, to_file_error, to_unformatted_disk_error, to_volume_error},
    format::FormatV3,
    fs::{O_APPEND, O_CREATE, O_RDONLY, O_TRUNC, O_WRONLY, access, lstat, lstat_std, remove, remove_all_std, remove_std, rename},
-    is_quota_mutation_fence_path, os,
+    os,
    os::{check_path_length, is_dir_not_empty_error, is_empty_dir, is_root_disk, rename_all, rename_all_ignore_missing_source},
-    quota_mutation_fence_path,
 };
 use crate::erasure::coding::{self, bitrot_verify};
 use crate::runtime::sources as runtime_sources;
@@ -61,7 +55,9 @@ use std::collections::HashMap;
 use std::collections::HashSet;
 use std::fmt::Debug;
 use std::io::{Error as IoError, SeekFrom};
-use std::sync::atomic::{AtomicBool, AtomicU32, AtomicUsize, Ordering};
+#[cfg(target_os = "linux")]
+use std::sync::atomic::AtomicBool;
+use std::sync::atomic::{AtomicU32, Ordering};
 use std::sync::{Arc, OnceLock};
 use std::time::Duration;
 use std::{
@@ -2028,17 +2024,14 @@ static RENAME_DATA_REMOVE_DST_BASE_BEFORE_COMMIT: std::sync::Mutex<Option<(Strin
 #[cfg(test)]
 type InlinePreparationHook = Box<dyn FnOnce() + Send>;
 #[cfg(test)]
-type RenameDataPublicationHookKey = (PathBuf, String, String);
-#[cfg(test)]
 static INLINE_PREPARATION_BEFORE_BACKUP: std::sync::LazyLock<std::sync::Mutex<HashMap<String, InlinePreparationHook>>> =
    std::sync::LazyLock::new(|| std::sync::Mutex::new(HashMap::new()));
 #[cfg(test)]
 static INLINE_BEFORE_FILE_SYNC_ADMISSION: std::sync::LazyLock<std::sync::Mutex<HashMap<String, InlinePreparationHook>>> =
    std::sync::LazyLock::new(|| std::sync::Mutex::new(HashMap::new()));
 #[cfg(test)]
-static RENAME_DATA_AFTER_FIRST_PUBLICATION: std::sync::LazyLock<
-    std::sync::Mutex<HashMap<RenameDataPublicationHookKey, InlinePreparationHook>>,
-> = std::sync::LazyLock::new(|| std::sync::Mutex::new(HashMap::new()));
+static RENAME_DATA_AFTER_FIRST_PUBLICATION: std::sync::LazyLock<std::sync::Mutex<HashMap<String, InlinePreparationHook>>> =
+    std::sync::LazyLock::new(|| std::sync::Mutex::new(HashMap::new()));
 #[cfg(test)]
 static OWNED_FILE_WRITE_BEFORE_OPEN: std::sync::LazyLock<std::sync::Mutex<HashMap<PathBuf, InlinePreparationHook>>> =
    std::sync::LazyLock::new(|| std::sync::Mutex::new(HashMap::new()));
@@ -2110,11 +2103,11 @@ fn set_inline_before_file_sync_admission(dst_path: &str, hook: impl FnOnce() + S
 }

 #[cfg(test)]
-fn set_rename_data_after_first_publication(root: &Path, dst_volume: &str, dst_path: &str, hook: impl FnOnce() + Send + 'static) {
+fn set_rename_data_after_first_publication(dst_path: &str, hook: impl FnOnce() + Send + 'static) {
    RENAME_DATA_AFTER_FIRST_PUBLICATION
        .lock()
        .expect("test publication hook lock should not be poisoned")
-        .insert((root.to_path_buf(), dst_volume.to_string(), dst_path.to_string()), Box::new(hook));
+        .insert(dst_path.to_string(), Box::new(hook));
 }

 #[cfg(test)]
@@ -2266,11 +2259,11 @@ fn run_inline_before_file_sync_admission(dst_path: &str) {
 }

 #[cfg(test)]
-fn run_rename_data_after_first_publication(root: &Path, dst_volume: &str, dst_path: &str) {
+fn run_rename_data_after_first_publication(dst_path: &str) {
    let hook = RENAME_DATA_AFTER_FIRST_PUBLICATION
        .lock()
        .expect("test publication hook lock should not be poisoned")
-        .remove(&(root.to_path_buf(), dst_volume.to_string(), dst_path.to_string()));
+        .remove(dst_path);
    if let Some(hook) = hook {
        hook();
    }
@@ -2368,6 +2361,9 @@ async fn remove_dst_base_before_commit(
 #[cfg(not(test))]
 fn run_inline_preparation_before_backup(_dst_path: &str) {}

+#[cfg(not(test))]
+fn run_rename_data_after_first_publication(_dst_path: &str) {}
+
 #[cfg(not(test))]
 fn should_fail_after_delete_data_staged(_path: &str) -> bool {
    false
@@ -4755,25 +4751,6 @@ struct SnapshotLeaseEntry {
    tokens: HashSet<SnapshotLeaseToken>,
    pending_delete: Option<DeleteOptions>,
    deleting: bool,
-    mutation_fence: Option<Arc<QuotaMutationFenceState>>,
-}
-
-#[derive(Default)]
-struct QuotaMutationFenceState {
-    revoked: AtomicBool,
-    running: AtomicUsize,
-    notify: Notify,
-}
-
-struct QuotaMutationFenceClaim {
-    state: Arc<QuotaMutationFenceState>,
-}
-
-impl Drop for QuotaMutationFenceClaim {
-    fn drop(&mut self) {
-        self.state.running.fetch_sub(1, Ordering::AcqRel);
-        self.state.notify.notify_waiters();
-    }
 }

 #[derive(Default)]
@@ -7338,34 +7315,6 @@ fn normalize_path_components(path: impl AsRef<Path>) -> PathBuf {
 }

 impl LocalDisk {
-    async fn claim_quota_mutation_fence(
-        &self,
-        volume: &str,
-        path: &str,
-        token: SnapshotLeaseToken,
-    ) -> Result<Arc<QuotaMutationFenceClaim>> {
-        let key = SnapshotLeaseKey {
-            volume: RUSTFS_META_BUCKET.to_string(),
-            path: quota_mutation_fence_path(volume, path),
-        };
-        let state = {
-            let registry = self.snapshot_leases.lock().await;
-            let entry = registry.entries.get(&key).ok_or(DiskError::FileNotFound)?;
-            let state = entry.mutation_fence.as_ref().ok_or(DiskError::FileNotFound)?;
-            if !entry.tokens.contains(&token) || state.revoked.load(Ordering::Acquire) {
-                return Err(DiskError::FileNotFound);
-            }
-            state.running.fetch_add(1, Ordering::AcqRel);
-            Arc::clone(state)
-        };
-        if state.revoked.load(Ordering::Acquire) {
-            state.running.fetch_sub(1, Ordering::AcqRel);
-            state.notify.notify_waiters();
-            return Err(DiskError::FileNotFound);
-        }
-        Ok(Arc::new(QuotaMutationFenceClaim { state }))
-    }
-
    async fn reserve_version_delete(&self, volume: &str, object: &str, data_dir: Uuid, rollback_dir: Uuid) -> Result<bool> {
        let path = format!("{object}/{data_dir}");
        let data_path = self.io_get_object_path(volume, &path)?;
@@ -8689,41 +8638,17 @@ impl DiskAPI for LocalDisk {
        &self,
        src_volume: &str,
        src_path: &str,
-        fi: FileInfo,
+        mut fi: FileInfo,
        dst_volume: &str,
        dst_path: &str,
    ) -> Result<RenameDataResp> {
        crate::hp_guard!("LocalDisk::rename_data");
-        let mut fi = fi;
        // A non-force DeleteBucket must not remove a directory while a local
        // object commit is publishing into it. The peer's empty scan remains
        // optimistic; this lease establishes the local commit/delete order and
        // remains owned by any blocking syscall that outlives async cancellation.
        let destination_object_path = self.io_get_object_path(dst_volume, dst_path)?;
-        let quota_fence_token =
-            match rustfs_utils::http::metadata_compat::get_consistent_str(&fi.metadata, QUOTA_MUTATION_FENCE_METADATA_SUFFIX) {
-                Some(value) => {
-                    let token = Uuid::parse_str(value).map_err(|_| DiskError::FileCorrupt)?;
-                    Some(SnapshotLeaseToken::from_slice(token.as_bytes())?)
-                }
-                None if rustfs_utils::http::metadata_compat::contains_key_str(
-                    &fi.metadata,
-                    QUOTA_MUTATION_FENCE_METADATA_SUFFIX,
-                ) =>
-                {
-                    return Err(DiskError::FileCorrupt);
-                }
-                None => None,
-            };
-        rustfs_utils::http::metadata_compat::remove_str(&mut fi.metadata, QUOTA_MUTATION_FENCE_METADATA_SUFFIX);
-        let quota_fence_claim = match quota_fence_token {
-            Some(token) => Some(self.claim_quota_mutation_fence(dst_volume, dst_path, token).await?),
-            None => None,
-        };
        let mutation_lease = os::acquire_rename_data_mutation_lease(&self.root, dst_volume, &destination_object_path).await;
-        if let Some(claim) = quota_fence_claim {
-            mutation_lease.attach_external_guard(claim);
-        }
        if fi.is_legacy_indexed_delete_marker() {
            fi.erasure.index = 0;
        }
@@ -9016,9 +8941,8 @@ impl DiskAPI for LocalDisk {
                .await?;
                return Err(err);
            }
-            #[cfg(test)]
            if has_data_dir_path.is_some() {
-                run_rename_data_after_first_publication(&self.root, dst_volume, dst_path);
+                run_rename_data_after_first_publication(dst_path);
            }

            // Crash-consistency injection: hard power loss after the data dir
@@ -9250,7 +9174,7 @@ impl DiskAPI for LocalDisk {

            if let Some(src_file_path_parent) = src_file_path.parent() {
                if src_volume != super::RUSTFS_META_MULTIPART_BUCKET {
-                    let _ = std::fs::remove_dir(src_file_path_parent);
+                    let _ = remove_std(src_file_path_parent);
                } else {
                    let _ = self
                        .delete_file(&dst_volume_dir, &src_file_path_parent.to_path_buf(), true, false)
@@ -9451,8 +9375,7 @@ impl DiskAPI for LocalDisk {
                    let _ = remove_file_if_exists(staged_backup);
                    return Err(err);
                }
-                #[cfg(test)]
-                run_rename_data_after_first_publication(&self.root, dst_volume, dst_path);
+                run_rename_data_after_first_publication(dst_path);
                if sync {
                    file_sync_admission = Some(
                        os::acquire_file_sync_admission(self.file_sync_permits.clone())
@@ -9576,7 +9499,7 @@ impl DiskAPI for LocalDisk {
            if let Some(ref cleanup) = cleanup_path {
                let _ = self.delete_file(&dst_volume_dir, cleanup, true, false).await;
            } else if let Some(parent) = src_file_path.parent() {
-                let _ = std::fs::remove_dir(parent);
+                let _ = remove_std(parent);
            }

            // Heal reuses a version's `data_dir` and lands the rebuilt shard on
@@ -9715,26 +9638,11 @@ impl DiskAPI for LocalDisk {
    }

    async fn acquire_snapshot_lease(&self, volume: &str, path: &str) -> Result<SnapshotLeaseToken> {
+        let file_path = self.io_get_object_path(volume, path)?;
        let key = SnapshotLeaseKey {
            volume: volume.to_string(),
            path: path.to_string(),
        };
-        if volume == RUSTFS_META_BUCKET && is_quota_mutation_fence_path(path) {
-            let mut registry = self.snapshot_leases.lock().await;
-            let entry = registry.entries.entry(key).or_default();
-            let state = entry
-                .mutation_fence
-                .get_or_insert_with(|| Arc::new(QuotaMutationFenceState::default()));
-            if state.revoked.load(Ordering::Acquire) {
-                return Err(DiskError::FileNotFound);
-            }
-            let token = SnapshotLeaseToken::new();
-            entry.tokens.insert(token);
-            return Ok(token);
-        }
-
-        let file_path = self.io_get_object_path(volume, path)?;
-        let _mutation_lease = os::acquire_rename_data_mutation_lease(&self.root, volume, &file_path).await;
        let token = {
            let mut registry = self.snapshot_leases.lock().await;
            if registry.entries.get(&key).is_some_and(|entry| entry.deleting) {
@@ -9762,48 +9670,6 @@ impl DiskAPI for LocalDisk {
            volume: volume.to_string(),
            path: path.to_string(),
        };
-        if volume == RUSTFS_META_BUCKET && is_quota_mutation_fence_path(path) {
-            if !token.is_revoke_all() {
-                let mut registry = self.snapshot_leases.lock().await;
-                let Some(entry) = registry.entries.get_mut(&key) else {
-                    return Ok(());
-                };
-                entry.tokens.remove(&token);
-                let removable = entry.tokens.is_empty()
-                    && entry
-                        .mutation_fence
-                        .as_ref()
-                        .is_none_or(|state| state.running.load(Ordering::Acquire) == 0);
-                if removable {
-                    registry.entries.remove(&key);
-                }
-                return Ok(());
-            }
-            let state = {
-                let mut registry = self.snapshot_leases.lock().await;
-                let Some(entry) = registry.entries.get_mut(&key) else {
-                    return Ok(());
-                };
-                let Some(state) = entry.mutation_fence.as_ref().cloned() else {
-                    registry.entries.remove(&key);
-                    return Ok(());
-                };
-                state.revoked.store(true, Ordering::Release);
-                entry.tokens.clear();
-                state
-            };
-            loop {
-                let notified = state.notify.notified();
-                tokio::pin!(notified);
-                notified.as_mut().enable();
-                if state.running.load(Ordering::Acquire) == 0 {
-                    break;
-                }
-                notified.await;
-            }
-            self.snapshot_leases.lock().await.entries.remove(&key);
-            return Ok(());
-        }
        let opts = {
            let mut registry = self.snapshot_leases.lock().await;
            let Some(entry) = registry.entries.get_mut(&key) else {
@@ -9974,12 +9840,6 @@ impl DiskAPI for LocalDisk {
        opts: &ReadOptions,
    ) -> Result<FileInfo> {
        crate::hp_guard!("LocalDisk::read_version");
-        let stage_metrics_enabled = rustfs_io_metrics::get_stage_metrics_enabled();
-        let metrics_path = if stage_metrics_enabled && crate::bucket::utils::is_meta_bucketname(volume) {
-            GET_OBJECT_PATH_INTERNAL_META
-        } else {
-            GET_OBJECT_PATH_LEGACY_DUPLEX
-        };
        if !org_volume.is_empty() {
            let org_volume_path = self.io_get_bucket_path(org_volume)?;
            if !skip_access_checks(org_volume) {
@@ -9989,46 +9849,36 @@ impl DiskAPI for LocalDisk {
            }
        }

-        let path_resolve_start = get_stage_timer_if_enabled(stage_metrics_enabled);
        let file_path = self.io_get_object_path(volume, path)?;
        let volume_dir = self.io_get_bucket_path(volume)?;
-        record_get_stage_duration_if_enabled(metrics_path, GET_STAGE_READ_VERSION_PATH_RESOLVE, path_resolve_start);

-        let path_check_start = get_stage_timer_if_enabled(stage_metrics_enabled);
        check_path_length(file_path.to_string_lossy().as_ref())?;
-        record_get_stage_duration_if_enabled(metrics_path, GET_STAGE_READ_VERSION_PATH_CHECK, path_check_start);

        let read_data = opts.read_data;

-        let xlmeta_read_start = get_stage_timer_if_enabled(stage_metrics_enabled);
-        let raw_read_result = self.read_raw(volume, volume_dir.clone(), file_path, read_data).await;
-        record_get_stage_duration_if_enabled(metrics_path, GET_STAGE_READ_VERSION_XLMETA_READ, xlmeta_read_start);
-        let (data, _) = raw_read_result.map_err(|e| {
-            if e == DiskError::FileNotFound && !version_id.is_empty() {
-                DiskError::FileVersionNotFound
-            } else {
-                e
-            }
-        })?;
+        let (data, _) = self
+            .read_raw(volume, volume_dir.clone(), file_path, read_data)
+            .await
+            .map_err(|e| {
+                if e == DiskError::FileNotFound && !version_id.is_empty() {
+                    DiskError::FileVersionNotFound
+                } else {
+                    e
+                }
+            })?;

-        let decode_start = get_stage_timer_if_enabled(stage_metrics_enabled);
-        let file_info_result: Result<FileInfo> = (|| {
-            let fi = get_file_info(
-                &data,
-                volume,
-                path,
-                version_id,
-                FileInfoOpts {
-                    data: read_data,
-                    include_free_versions: opts.incl_free_versions,
-                    include_part_checksums: false,
-                },
-            )?;
-            fi.validate_for_metadata_read()?;
-            Ok(fi)
-        })();
-        record_get_stage_duration_if_enabled(metrics_path, GET_STAGE_READ_VERSION_DECODE, decode_start);
-        let mut fi = file_info_result?;
+        let mut fi = get_file_info(
+            &data,
+            volume,
+            path,
+            version_id,
+            FileInfoOpts {
+                data: read_data,
+                include_free_versions: opts.incl_free_versions,
+            },
+        )?;
+
+        fi.validate_for_metadata_read()?;
        if fi.is_canonical_delete_marker() {
            return Ok(fi);
        }
@@ -10582,19 +10432,6 @@ impl DiskAPI for LocalDisk {
    }
 }

-impl LocalDisk {
-    pub(crate) async fn rename_data_borrowed(
-        &self,
-        src_volume: &str,
-        src_path: &str,
-        fi: &FileInfo,
-        dst_volume: &str,
-        dst_path: &str,
-    ) -> Result<RenameDataResp> {
-        <Self as DiskAPI>::rename_data(self, src_volume, src_path, fi.clone(), dst_volume, dst_path).await
-    }
-}
-
 async fn wait_for_startup_cleanup_signal(
    startup_cleanup_ready: &AtomicU32,
    startup_cleanup_notify: &Notify,
@@ -10724,108 +10561,6 @@ mod test {
        meta.marshal_msg().expect("test metadata should encode")
    }

-    #[test]
-    #[serial_test::serial]
-    fn read_version_records_local_metadata_stage_breakdown() {
-        let runtime = tokio::runtime::Builder::new_current_thread()
-            .enable_all()
-            .build()
-            .expect("test runtime should be created");
-        let recorder = crate::test_metrics::CapturingRecorder::default();
-        let previous_gate = rustfs_io_metrics::get_stage_metrics_enabled();
-        rustfs_io_metrics::set_get_stage_metrics_enabled(true);
-
-        metrics::with_local_recorder(&recorder, || {
-            runtime.block_on(async {
-                let dir = tempfile::tempdir().expect("temp dir should be created");
-                let endpoint =
-                    Endpoint::try_from(dir.path().to_str().expect("temp dir should be utf8")).expect("endpoint should parse");
-                let disk = LocalDisk::new(&endpoint, false).await.expect("local disk should be created");
-                let bucket = "bucket";
-                let object = "stage-breakdown";
-                ensure_test_volume(&disk, bucket).await;
-
-                let object_dir = dir.path().join(bucket).join(object);
-                fs::create_dir_all(&object_dir)
-                    .await
-                    .expect("object directory should be created");
-                fs::write(
-                    object_dir.join(STORAGE_FORMAT_FILE),
-                    test_meta(test_file_info(object, Uuid::new_v4(), None, Some(Bytes::from_static(b"inline")))),
-                )
-                .await
-                .expect("object metadata should be written");
-
-                disk.read_version(
-                    "",
-                    bucket,
-                    object,
-                    "",
-                    &ReadOptions {
-                        read_data: true,
-                        ..Default::default()
-                    },
-                )
-                .await
-                .expect("read_version should succeed");
-
-                let meta_object = "stage-breakdown-meta";
-                let meta_object_dir = dir.path().join(RUSTFS_META_BUCKET).join(meta_object);
-                fs::create_dir_all(&meta_object_dir)
-                    .await
-                    .expect("internal metadata object directory should be created");
-                fs::write(
-                    meta_object_dir.join(STORAGE_FORMAT_FILE),
-                    test_meta(test_file_info(meta_object, Uuid::new_v4(), None, Some(Bytes::from_static(b"meta")))),
-                )
-                .await
-                .expect("internal metadata should be written");
-
-                disk.read_version(
-                    "",
-                    RUSTFS_META_BUCKET,
-                    meta_object,
-                    "",
-                    &ReadOptions {
-                        read_data: true,
-                        ..Default::default()
-                    },
-                )
-                .await
-                .expect("internal metadata read_version should succeed");
-            });
-        });
-        rustfs_io_metrics::set_get_stage_metrics_enabled(previous_gate);
-
-        for stage in [
-            GET_STAGE_READ_VERSION_PATH_RESOLVE,
-            GET_STAGE_READ_VERSION_PATH_CHECK,
-            GET_STAGE_READ_VERSION_XLMETA_READ,
-            GET_STAGE_READ_VERSION_DECODE,
-        ] {
-            assert_eq!(
-                recorder
-                    .histogram_values(
-                        "rustfs_io_get_object_stage_duration_seconds",
-                        &[("path", GET_OBJECT_PATH_LEGACY_DUPLEX), ("stage", stage)]
-                    )
-                    .len(),
-                1,
-                "{stage} should be recorded once for user-bucket LocalDisk::read_version"
-            );
-            assert_eq!(
-                recorder
-                    .histogram_values(
-                        "rustfs_io_get_object_stage_duration_seconds",
-                        &[("path", GET_OBJECT_PATH_INTERNAL_META), ("stage", stage)]
-                    )
-                    .len(),
-                1,
-                "{stage} should be recorded once for internal-meta LocalDisk::read_version"
-            );
-        }
-    }
-
    #[test]
    fn inline_metadata_rollback_dir_avoids_real_data_dir_collision() {
        let target_version = Uuid::parse_str("11111111-2222-3333-4444-555555555555").expect("version id should parse");
@@ -12704,10 +12439,6 @@ mod test {
            .join(RUSTFS_META_TMP_BUCKET)
            .join(tmp_object)
            .join(new_data_dir.to_string());
-        let tmp_parent = tmp_data_dir
-            .parent()
-            .expect("tmp data dir should have a parent")
-            .to_path_buf();
        fs::create_dir_all(&tmp_data_dir)
            .await
            .expect("new tmp data dir should be created");
@@ -12719,10 +12450,6 @@ mod test {
        disk.rename_data(RUSTFS_META_TMP_BUCKET, tmp_object, new_fi, bucket, object)
            .await
            .expect("rename_data should commit");
-        assert!(
-            !tmp_parent.exists(),
-            "successful non-inline commit should remove the empty staging parent"
-        );

        // The tmp xl.meta write point uses SyncMode::FileOnly: its parent dir
        // ({tmp}/{tmp_object}) must not be fsynced.
@@ -12927,9 +12654,6 @@ mod test {
        let tmp_object = "tmp-new-inline";
        ensure_test_volume(&disk, bucket).await;
        ensure_test_volume(&disk, RUSTFS_META_TMP_BUCKET).await;
-        let tmp_parent = disk
-            .get_object_path(RUSTFS_META_TMP_BUCKET, tmp_object)
-            .expect("tmp parent should resolve");

        let _mode = durability_mode_override::set(DurabilityMode::Strict);
        let version_id = Uuid::parse_str("99999999-9999-9999-9999-999999999999").expect("version id should parse");
@@ -12938,7 +12662,6 @@ mod test {
        disk.rename_data(RUSTFS_META_TMP_BUCKET, tmp_object, new_fi, bucket, object)
            .await
            .expect("inline rename_data should commit the new object");
-        assert!(!tmp_parent.exists(), "successful inline commit should remove the empty staging parent");

        let bucket_dir = disk.get_bucket_path(bucket).expect("bucket path should resolve");
        let prefix_dir = disk.get_object_path(bucket, "prefix").expect("prefix path should resolve");
@@ -12962,34 +12685,6 @@ mod test {
        );
    }

-    #[tokio::test]
-    async fn rename_data_inline_preserves_non_empty_staging_parent() {
-        use tempfile::tempdir;
-
-        let dir = tempdir().expect("temp dir should be created");
-        let endpoint = Endpoint::try_from(dir.path().to_str().expect("temp dir should be utf8")).expect("endpoint should parse");
-        let disk = LocalDisk::new(&endpoint, false).await.expect("local disk should be created");
-        let bucket = "inline-staging-sentinel-bucket";
-        let object = "inline-object";
-        let tmp_object = "inline-stage-with-sentinel";
-        ensure_test_volume(&disk, bucket).await;
-        ensure_test_volume(&disk, RUSTFS_META_TMP_BUCKET).await;
-
-        let tmp_parent = disk
-            .get_object_path(RUSTFS_META_TMP_BUCKET, tmp_object)
-            .expect("tmp parent should resolve");
-        fs::create_dir_all(&tmp_parent).await.expect("tmp parent should be created");
-        let sentinel = tmp_parent.join("sentinel");
-        fs::write(&sentinel, b"keep").await.expect("sentinel should be written");
-
-        let fi = test_file_info(object, Uuid::new_v4(), None, Some(Bytes::from_static(b"inline-payload")));
-        disk.rename_data(RUSTFS_META_TMP_BUCKET, tmp_object, fi, bucket, object)
-            .await
-            .expect("non-empty staging cleanup must not negate the committed object");
-
-        assert_eq!(fs::read(&sentinel).await.expect("sentinel should remain"), b"keep");
-    }
-
    #[cfg(unix)]
    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
    #[allow(clippy::await_holding_lock)]
@@ -13149,7 +12844,7 @@ mod test {
        let replacement_staging_parent_for_hook = replacement_staging_parent.clone();
        let staged_metadata_for_hook = staged_metadata.clone();
        let replacement_staged_metadata_for_hook = replacement_staged_metadata.clone();
-        set_rename_data_after_first_publication(&disk.root, bucket, object, move || {
+        set_rename_data_after_first_publication(object, move || {
            std::fs::rename(&object_dir_for_hook, &replacement_dir_for_hook)
                .expect_err("the destination object identity must remain pinned until xl.meta commits");
            std::fs::rename(&staging_parent_for_hook, &replacement_staging_parent_for_hook)
@@ -13164,10 +12859,7 @@ mod test {
            .expect("non-inline rename_data should commit");

        assert!(!replacement_dir.exists(), "the destination object directory must not be replaced");
-        assert!(
-            !staging_parent.exists(),
-            "successful commit should remove the empty staging parent after releasing its guard"
-        );
+        assert!(staging_parent.exists(), "the guarded staging parent must retain its identity");
        assert!(
            !replacement_staging_parent.exists(),
            "the staging parent must not be replaced between data and metadata publication"
@@ -13416,7 +13108,7 @@ mod test {
        let replacement_dir_for_hook = replacement_dir.clone();
        let staged_metadata_for_hook = staged_metadata.clone();
        let replacement_staged_metadata_for_hook = replacement_staged_metadata.clone();
-        set_rename_data_after_first_publication(&disk.root, bucket, object, move || {
+        set_rename_data_after_first_publication(object, move || {
            std::fs::rename(&object_dir_for_hook, &replacement_dir_for_hook)
                .expect_err("the destination object identity must remain pinned after publishing its rollback backup");
            std::fs::rename(&staged_metadata_for_hook, &replacement_staged_metadata_for_hook)
@@ -13782,7 +13474,7 @@ mod test {

        let (entered_tx, entered_rx) = mpsc::channel();
        let (release_tx, release_rx) = mpsc::channel();
-        set_rename_data_after_first_publication(&disk.root, bucket, object, move || {
+        set_rename_data_after_first_publication(object, move || {
            entered_tx.send(()).expect("signal first publication");
            release_rx.recv().expect("wait while delete_volume is blocked");
        });
@@ -14376,7 +14068,7 @@ mod test {

        let (published_tx, published_rx) = mpsc::channel();
        let (release_tx, release_rx) = mpsc::channel();
-        set_rename_data_after_first_publication(&disk.root, bucket, object, move || {
+        set_rename_data_after_first_publication(object, move || {
            published_tx.send(()).expect("signal backup publication");
            release_rx.recv().expect("wait for lock-order assertion");
        });
@@ -19031,48 +18723,6 @@ mod test {
        assert!(matches!(disk.read_all(volume, &first_part).await, Err(DiskError::FileNotFound)));
    }

-    #[tokio::test]
-    async fn quota_mutation_fence_revoke_waits_for_active_claim_and_rejects_late_claims() {
-        use tempfile::tempdir;
-
-        let root_dir = tempdir().expect("temp dir should be created");
-        let endpoint = Endpoint::try_from(root_dir.path().to_string_lossy().as_ref()).expect("endpoint should parse");
-        let disk = Arc::new(LocalDisk::new(&endpoint, false).await.expect("local disk should be created"));
-        let bucket = "quota-fence-volume";
-        let object = "object";
-        let fence_path = quota_mutation_fence_path(bucket, object);
-        let token = disk
-            .acquire_snapshot_lease(RUSTFS_META_BUCKET, &fence_path)
-            .await
-            .expect("quota mutation token should be prepared");
-        let claim = disk
-            .claim_quota_mutation_fence(bucket, object, token)
-            .await
-            .expect("prepared token should be claimable");
-
-        let release_disk = Arc::clone(&disk);
-        let mut release = tokio::spawn(async move {
-            release_disk
-                .release_snapshot_lease(RUSTFS_META_BUCKET, &fence_path, SnapshotLeaseToken::revoke_all())
-                .await
-        });
-        assert!(
-            tokio::time::timeout(Duration::from_millis(50), &mut release).await.is_err(),
-            "revoke must wait until an already claimed mutation has finished"
-        );
-
-        drop(claim);
-        tokio::time::timeout(Duration::from_secs(1), release)
-            .await
-            .expect("revoke should wake after the final claim drops")
-            .expect("revoke task should not panic")
-            .expect("revoke should succeed");
-        assert!(matches!(
-            disk.claim_quota_mutation_fence(bucket, object, token).await,
-            Err(DiskError::FileNotFound)
-        ));
-    }
-
    #[tokio::test]
    async fn delete_version_keeps_later_part_until_snapshot_release() {
        use tempfile::tempdir;
@@ -55,7 +55,6 @@ pub fn part_transaction_path(part_path: &str) -> String {

 use crate::cluster::rpc::RemoteDisk;
 use crate::cluster::rpc::build_internode_data_transport_from_env;
-use crate::disk::disk_store::DiskStoreRenameDataExt;
 use crate::disk::disk_store::LocalDiskWrapper;
 use crate::disk::health_state::RuntimeDriveHealthState;
 use crate::disk::local::ScanGuard;
@@ -66,35 +65,12 @@ use error::{Error, Result};
 use local::LocalDisk;
 use rustfs_filemeta::{FileInfo, ObjectPartInfo, RawFileInfo};
 use rustfs_madmin::info_commands::DiskMetrics;
-use rustfs_rio::ChunkReaderBox;
 use serde::{Deserialize, Serialize};
 use std::{fmt::Debug, path::PathBuf, sync::Arc, time::Duration};
 use time::OffsetDateTime;
 use tokio::io::{AsyncRead, AsyncWrite};
 use uuid::Uuid;

-const QUOTA_MUTATION_FENCE_PREFIX: &str = "tmp/quota-mutation-fences/";
-pub(crate) const QUOTA_MUTATION_FENCE_METADATA_SUFFIX: &str = "quota-mutation-fence-token";
-
-pub(crate) fn quota_mutation_fence_path(bucket: &str, object: &str) -> String {
-    use sha2::{Digest, Sha256};
-
-    let mut input = Vec::with_capacity(bucket.len() + object.len() + 1);
-    input.extend_from_slice(bucket.as_bytes());
-    input.push(0);
-    input.extend_from_slice(object.as_bytes());
-    let digest = Sha256::digest(input);
-    format!(
-        "{QUOTA_MUTATION_FENCE_PREFIX}{}",
-        hex_simd::encode_to_string(digest, hex_simd::AsciiCase::Lower)
-    )
-}
-
-pub(crate) fn is_quota_mutation_fence_path(path: &str) -> bool {
-    path.strip_prefix(QUOTA_MUTATION_FENCE_PREFIX)
-        .is_some_and(|digest| digest.len() == 64 && digest.bytes().all(|byte| byte.is_ascii_hexdigit()))
-}
-
 pub type DiskStore = Arc<Disk>;

 pub type FileReader = Box<dyn AsyncRead + Send + Sync + Unpin>;
@@ -119,20 +95,6 @@ impl SnapshotLeaseToken {
    pub fn as_bytes(&self) -> &[u8; 16] {
        self.0.as_bytes()
    }
-
-    pub(crate) fn as_uuid(self) -> Uuid {
-        self.0
-    }
-
-    #[doc(hidden)]
-    pub fn revoke_all() -> Self {
-        Self(Uuid::nil())
-    }
-
-    #[doc(hidden)]
-    pub fn is_revoke_all(self) -> bool {
-        self.0.is_nil()
-    }
 }

 impl Default for SnapshotLeaseToken {
@@ -435,8 +397,10 @@ impl DiskAPI for Disk {
        dst_volume: &str,
        dst_path: &str,
    ) -> Result<RenameDataResp> {
-        self.rename_data_borrowed(src_volume, src_path, &fi, dst_volume, dst_path)
-            .await
+        match self {
+            Disk::Local(local_disk) => local_disk.rename_data(src_volume, src_path, fi, dst_volume, dst_path).await,
+            Disk::Remote(remote_disk) => remote_disk.rename_data(src_volume, src_path, fi, dst_volume, dst_path).await,
+        }
    }

    #[tracing::instrument(level = "trace", skip_all)]
@@ -463,19 +427,6 @@ impl DiskAPI for Disk {
        }
    }

-    async fn read_file_stream_chunks(
-        &self,
-        volume: &str,
-        path: &str,
-        offset: usize,
-        length: usize,
-    ) -> Result<Option<ChunkReaderBox>> {
-        match self {
-            Disk::Local(_) => Ok(None),
-            Disk::Remote(remote_disk) => remote_disk.read_file_stream_chunks(volume, path, offset, length).await,
-        }
-    }
-
    #[tracing::instrument(level = "trace", skip_all)]
    async fn read_file_mmap_copy(&self, volume: &str, path: &str, offset: usize, length: usize) -> Result<Bytes> {
        match self {
@@ -666,30 +617,6 @@ impl DiskAPI for Disk {
    }
 }

-impl Disk {
-    pub(crate) async fn rename_data_borrowed(
-        &self,
-        src_volume: &str,
-        src_path: &str,
-        fi: &FileInfo,
-        dst_volume: &str,
-        dst_path: &str,
-    ) -> Result<RenameDataResp> {
-        match self {
-            Disk::Local(local_disk) => {
-                local_disk
-                    .rename_data_borrowed(src_volume, src_path, fi, dst_volume, dst_path)
-                    .await
-            }
-            Disk::Remote(remote_disk) => {
-                remote_disk
-                    .rename_data_borrowed(src_volume, src_path, fi, dst_volume, dst_path)
-                    .await
-            }
-        }
-    }
-}
-
 impl Disk {
    pub async fn ns_scanner_server_epoch(&self) -> Result<Option<Uuid>> {
        match self {
@@ -938,18 +865,6 @@ pub trait DiskAPI: Debug + Send + Sync + 'static {
    async fn read_file(&self, volume: &str, path: &str) -> Result<FileReader>;
    async fn read_file_stream(&self, volume: &str, path: &str, offset: usize, length: usize) -> Result<FileReader>;

-    /// Returns an owned-chunk stream when the backing transport can preserve
-    /// receive-buffer ownership. `None` retains the ordinary reader path.
-    async fn read_file_stream_chunks(
-        &self,
-        _volume: &str,
-        _path: &str,
-        _offset: usize,
-        _length: usize,
-    ) -> Result<Option<ChunkReaderBox>> {
-        Ok(None)
-    }
-
    /// File read using mmap-then-copy on Unix or an efficient read on non-Unix.
    async fn read_file_mmap_copy(&self, volume: &str, path: &str, offset: usize, length: usize) -> Result<Bytes>;

@@ -306,20 +306,12 @@ fn disk_namespace_mutation_lock(path: &Path) -> Arc<NamespaceMutationLock> {
 pub(crate) struct NamespaceMutationLease {
    _namespace_guard: OwnedMutexGuard<()>,
    _volume_guard: Option<OwnedRwLockReadGuard<()>>,
-    external_guard: Mutex<Option<Arc<dyn Send + Sync>>>,
-}
-
-impl NamespaceMutationLease {
-    pub(crate) fn attach_external_guard(&self, guard: Arc<dyn Send + Sync>) {
-        *self.external_guard.lock() = Some(guard);
-    }
 }

 async fn acquire_namespace_mutation_lease(path: &Path) -> Arc<NamespaceMutationLease> {
    Arc::new(NamespaceMutationLease {
        _namespace_guard: disk_namespace_mutation_lock(path).lock_owned().await,
        _volume_guard: None,
-        external_guard: Mutex::new(None),
    })
 }

@@ -335,7 +327,6 @@ pub(crate) async fn acquire_rename_data_mutation_lease(
    Arc::new(NamespaceMutationLease {
        _namespace_guard: namespace_guard,
        _volume_guard: Some(volume_guard),
-        external_guard: Mutex::new(None),
    })
 }

@@ -26,7 +26,6 @@ pub(crate) const GET_RECONSTRUCT_OUTCOME_SKIP_DATA_COMPLETE: &str = "skip_data_c
 pub(crate) const GET_RECONSTRUCT_OUTCOME_SKIP_EMPTY_PAYLOAD: &str = "skip_empty_payload";

 pub(crate) trait DecodeWorkspace: Send + Sync + 'static {
-    #[allow(dead_code, reason = "workspace width asserted by decode_reader tests (backlog#1823)")]
    fn shard_len(&self) -> usize;
 }

@@ -34,14 +33,11 @@ pub(crate) trait ErasureDecodeEngine: Send + Sync + 'static {
    type Workspace: DecodeWorkspace;

    fn data_shards(&self) -> usize;
-    #[allow(dead_code, reason = "engine trait facet asserted by decode_reader tests (backlog#1823)")]
    fn parity_shards(&self) -> usize;
    fn block_size(&self) -> usize;
    fn engine_name(&self) -> &'static str;

-    #[allow(dead_code, reason = "engine trait facet asserted by decode_reader tests (backlog#1823)")]
    fn supports_progressive_decode(&self) -> bool;
-    #[allow(dead_code, reason = "engine trait facet asserted by decode_reader tests (backlog#1823)")]
    fn supports_aligned_shards(&self) -> bool;

    fn prepare_workspace(&self, shard_len: usize) -> io::Result<Self::Workspace>;
@@ -24,7 +24,6 @@ impl RustfsCodecDecodeWorkspace {
    }

    #[inline]
-    #[allow(dead_code, reason = "workspace width asserted by decode_reader tests (backlog#1823)")]
    pub(crate) fn shard_len(&self) -> usize {
        self.shard_len
    }
@@ -77,13 +76,6 @@ impl ShardBufferPool {
        self.buffers[index] = Some(buf);
    }

-    #[cfg(test)]
-    pub(crate) fn stored_allocation(&self, index: usize) -> Option<(*const u8, usize)> {
-        self.buffers
-            .get(index)
-            .and_then(|buf| buf.as_ref().map(|buf| (buf.as_ptr(), buf.capacity())))
-    }
-
    #[cfg(test)]
    fn stored_capacity(&self, index: usize) -> Option<usize> {
        self.buffers.get(index).and_then(|buf| buf.as_ref().map(Vec::capacity))
@@ -14,10 +14,7 @@

 use pin_project_lite::pin_project;
 use rustfs_utils::HashAlgorithm;
-use std::future::poll_fn;
 use std::io::IoSlice;
-use std::pin::Pin;
-use std::task::{Context, Poll};
 use std::time::Duration;
 use tokio::io::{AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt};
 use tracing::error;
@@ -26,18 +23,6 @@ const LOG_COMPONENT_ECSTORE: &str = "ecstore";
 const LOG_SUBSYSTEM_ERASURE: &str = "erasure";
 const EVENT_BITROT_SHORT_SHARD_READ: &str = "bitrot_short_shard_read";
 const EVENT_BITROT_HASH_MISMATCH: &str = "bitrot_hash_mismatch";
-const MAX_RETAINED_CHUNKS_PER_BLOCK: usize = 64;
-const MAX_CHUNK_POLLS_PER_YIELD: usize = MAX_RETAINED_CHUNKS_PER_BLOCK + 1;
-
-/// Result of polling an optional owned-chunk handoff.
-pub enum ShardChunkRead {
-    /// The source does not support owned-chunk handoff and remains untouched.
-    Unsupported,
-    /// The source reached EOF.
-    Eof,
-    /// A non-empty chunk containing at most the requested number of bytes.
-    Chunk(bytes::Bytes),
-}

 /// A shard source that may already hold its bytes in memory.
 ///
@@ -57,12 +42,6 @@ pub trait ShardSource: AsyncRead + Send + Sync + Unpin {
    fn try_take_block(&mut self, _n: usize) -> Option<bytes::Bytes> {
        None
    }
-
-    /// Polls one owned chunk when the source supports chunk handoff.
-    /// `Unsupported` must leave the source untouched.
-    fn poll_read_chunk(self: Pin<&mut Self>, _cx: &mut Context<'_>, _max: usize) -> Poll<std::io::Result<ShardChunkRead>> {
-        Poll::Ready(Ok(ShardChunkRead::Unsupported))
-    }
 }

 /// Borrowed and owned byte slices are ordinary streaming sources: they carry no
@@ -96,9 +75,6 @@ pin_project! {
        // contiguous on-disk `[hash][data]` block so both are pulled in a single
        // pass; grown lazily and never shrunk.
        buf: Vec<u8>,
-        // Reused owned chunk vector for the remote HTTP fast path. Keeping the
-        // allocation with the reader avoids allocating once per bitrot block.
-        chunks: Vec<bytes::Bytes>,
        skip_verify: bool,
        last_verify_duration: Duration,
    }
@@ -115,7 +91,6 @@ where
            hash_algo: algo,
            shard_size,
            buf: Vec::new(),
-            chunks: Vec::new(),
            skip_verify,
            last_verify_duration: Duration::ZERO,
        }
@@ -125,11 +100,6 @@ where
        self.last_verify_duration
    }

-    #[cfg(test)]
-    pub(crate) fn inner_ref(&self) -> &R {
-        &self.inner
-    }
-
    /// Read a single (hash+data) block, verify hash, and copy `out.len()` bytes
    /// into `out`. Returns an error if the shard is short, the hash mismatches,
    /// or `out` is larger than one shard. On error `out`'s contents are
@@ -290,6 +260,11 @@ where

        let need = hash_size + want;

+        // In-memory fast path: the block is already resident, so slice it instead
+        // of copying it into the scratch buffer first (rustfs/backlog#1159). One
+        // copy (`extend_from_slice`) instead of two. A source that cannot serve
+        // `need` bytes returns `None` and falls through to the scratch path,
+        // keeping the short-read contract.
        if let Some(block) = self.inner.try_take_block(need) {
            let (data, verify) = split_and_verify(&self.hash_algo, self.skip_verify, &block)?;
            out.extend_from_slice(data);
@@ -297,126 +272,6 @@ where
            return Ok(want);
        }

-        self.chunks.clear();
-        let handed_off = {
-            let inner = &mut self.inner;
-            let chunks = &mut self.chunks;
-            let tail_buf = &mut self.buf;
-            let mut received = 0usize;
-            poll_fn(|cx| {
-                for _ in 0..MAX_CHUNK_POLLS_PER_YIELD {
-                    let next = match Pin::new(&mut *inner).poll_read_chunk(cx, need - received) {
-                        Poll::Ready(Ok(next)) => next,
-                        Poll::Ready(Err(err)) => return Poll::Ready(Err(err)),
-                        Poll::Pending => return Poll::Pending,
-                    };
-                    let chunk = match next {
-                        ShardChunkRead::Unsupported if received == 0 => return Poll::Ready(Ok(false)),
-                        ShardChunkRead::Unsupported => {
-                            return Poll::Ready(Err(std::io::Error::new(
-                                std::io::ErrorKind::InvalidData,
-                                "chunk handoff became unavailable after transferring data",
-                            )));
-                        }
-                        ShardChunkRead::Eof => {
-                            return Poll::Ready(Err(short_shard_read(received.saturating_sub(hash_size), want)));
-                        }
-                        ShardChunkRead::Chunk(chunk) => chunk,
-                    };
-
-                    if received == 0 {
-                        tail_buf.clear();
-                    }
-                    if chunk.is_empty() {
-                        return Poll::Ready(Err(std::io::Error::new(
-                            std::io::ErrorKind::InvalidData,
-                            "chunk handoff returned an empty chunk",
-                        )));
-                    }
-                    let remaining = need - received;
-                    if chunk.len() > remaining {
-                        return Poll::Ready(Err(std::io::Error::new(
-                            std::io::ErrorKind::InvalidData,
-                            "chunk handoff exceeded its requested boundary",
-                        )));
-                    }
-                    received += chunk.len();
-
-                    if chunks.len() == MAX_RETAINED_CHUNKS_PER_BLOCK {
-                        if tail_buf.is_empty() {
-                            tail_buf.reserve_exact(need - (received - chunk.len()));
-                        }
-                        tail_buf.extend_from_slice(&chunk);
-                    } else {
-                        chunks.push(chunk);
-                    }
-
-                    if received == need {
-                        return Poll::Ready(Ok(true));
-                    }
-                }
-                cx.waker().wake_by_ref();
-                Poll::Pending
-            })
-            .await?
-        };
-        if handed_off {
-            if self.chunks.len() == 1 && self.buf.is_empty() {
-                let block = &self.chunks[0];
-                let (data, verify) = split_and_verify(&self.hash_algo, self.skip_verify, block)?;
-                out.extend_from_slice(data);
-                self.last_verify_duration = verify;
-                return Ok(want);
-            }
-
-            let block_chunks = || {
-                self.chunks
-                    .iter()
-                    .map(|chunk| chunk.as_ref())
-                    .chain((!self.buf.is_empty()).then_some(self.buf.as_slice()))
-            };
-            if !self.skip_verify {
-                let verify_start = std::time::Instant::now();
-                let actual_hash = self
-                    .hash_algo
-                    .hash_encode_slices(block_chunks().scan(hash_size, |skip, chunk| {
-                        let start = (*skip).min(chunk.len());
-                        *skip -= start;
-                        Some(&chunk[start..])
-                    }));
-                let verify = verify_start.elapsed();
-                let mut hash_offset = 0;
-                let mut remaining = hash_size;
-                for chunk in block_chunks() {
-                    let take = remaining.min(chunk.len());
-                    if actual_hash.as_ref()[hash_offset..hash_offset + take] != chunk[..take] {
-                        error!(
-                            event = EVENT_BITROT_HASH_MISMATCH,
-                            component = LOG_COMPONENT_ECSTORE,
-                            subsystem = LOG_SUBSYSTEM_ERASURE,
-                            state = "failed",
-                            data_len = want,
-                            "bitrot hash mismatch"
-                        );
-                        return Err(std::io::Error::new(std::io::ErrorKind::InvalidData, "bitrot hash mismatch"));
-                    }
-                    hash_offset += take;
-                    remaining -= take;
-                    if remaining == 0 {
-                        break;
-                    }
-                }
-                self.last_verify_duration = verify;
-            }
-            let mut skip = hash_size;
-            for chunk in block_chunks() {
-                let start = skip.min(chunk.len());
-                skip -= start;
-                out.extend_from_slice(&chunk[start..]);
-            }
-            return Ok(want);
-        }
-
        // Streaming path: same single pass and same verification as `read`; only
        // the sink differs (`extend_from_slice` into `out` instead of
        // `copy_from_slice` into a pre-zeroed buffer).
@@ -822,167 +677,18 @@ impl BitrotWriterWrapper {

 #[cfg(test)]
 mod tests {
+    use super::ShardSource;
    use super::{
        BitrotReader, BitrotWriter, BitrotWriterWrapper, CustomWriter, bitrot_shard_file_size, bitrot_verify, write_all_vectored,
    };
-    use super::{MAX_RETAINED_CHUNKS_PER_BLOCK, ShardChunkRead, ShardSource};
-    use bytes::Bytes;
    use rustfs_utils::HashAlgorithm;
-    use std::collections::VecDeque;
-    use std::io::{self, Cursor, IoSlice};
-    use std::pin::Pin;
+    use std::io::{Cursor, IoSlice};
    use std::sync::{
        Arc,
        atomic::{AtomicUsize, Ordering},
    };
    use std::task::{Context, Poll};
-    use std::time::Duration;
-    use tokio::io::{AsyncRead, AsyncWrite, AsyncWriteExt, ReadBuf};
-
-    struct FragmentedSource {
-        chunks: VecDeque<Bytes>,
-    }
-
-    impl FragmentedSource {
-        fn new(bytes: Vec<u8>, fragment_sizes: &[usize]) -> Self {
-            let mut chunks = VecDeque::new();
-            let mut offset = 0;
-            for &size in fragment_sizes {
-                let end = (offset + size).min(bytes.len());
-                if offset < end {
-                    chunks.push_back(Bytes::copy_from_slice(&bytes[offset..end]));
-                }
-                offset = end;
-            }
-            if offset < bytes.len() {
-                chunks.push_back(Bytes::copy_from_slice(&bytes[offset..]));
-            }
-            Self { chunks }
-        }
-    }
-
-    impl AsyncRead for FragmentedSource {
-        fn poll_read(self: Pin<&mut Self>, _cx: &mut Context<'_>, _buf: &mut ReadBuf<'_>) -> Poll<io::Result<()>> {
-            Poll::Ready(Err(io::Error::other("fragmented source must use chunk handoff")))
-        }
-    }
-
-    impl ShardSource for FragmentedSource {
-        fn poll_read_chunk(mut self: Pin<&mut Self>, _cx: &mut Context<'_>, max: usize) -> Poll<io::Result<ShardChunkRead>> {
-            let Some(mut chunk) = self.chunks.pop_front() else {
-                return Poll::Ready(Ok(ShardChunkRead::Eof));
-            };
-            if chunk.len() > max {
-                self.chunks.push_front(chunk.split_off(max));
-                chunk.truncate(max);
-            }
-            Poll::Ready(Ok(ShardChunkRead::Chunk(chunk)))
-        }
-    }
-
-    struct GeneratedChunkSource {
-        bytes: Bytes,
-        offset: usize,
-        fragment_size: usize,
-        fail_at: Option<usize>,
-    }
-
-    impl GeneratedChunkSource {
-        fn new(bytes: Vec<u8>, fragment_size: usize) -> Self {
-            assert!(fragment_size > 0);
-            Self {
-                bytes: Bytes::from(bytes),
-                offset: 0,
-                fragment_size,
-                fail_at: None,
-            }
-        }
-
-        fn failing(bytes: Vec<u8>, fragment_size: usize, fail_at: usize) -> Self {
-            Self {
-                fail_at: Some(fail_at),
-                ..Self::new(bytes, fragment_size)
-            }
-        }
-    }
-
-    impl AsyncRead for GeneratedChunkSource {
-        fn poll_read(self: Pin<&mut Self>, _cx: &mut Context<'_>, _buf: &mut ReadBuf<'_>) -> Poll<io::Result<()>> {
-            Poll::Ready(Err(io::Error::other("generated source must use chunk handoff")))
-        }
-    }
-
-    impl ShardSource for GeneratedChunkSource {
-        fn poll_read_chunk(mut self: Pin<&mut Self>, _cx: &mut Context<'_>, max: usize) -> Poll<io::Result<ShardChunkRead>> {
-            if self.fail_at == Some(self.offset) {
-                return Poll::Ready(Err(rustfs_rio::new_test_internode_http_io_error(
-                    rustfs_rio::InternodeHttpErrorKind::BodyStreamAborted,
-                )));
-            }
-            if self.offset == self.bytes.len() {
-                return Poll::Ready(Ok(ShardChunkRead::Eof));
-            }
-            let error_limit = self.fail_at.unwrap_or(self.bytes.len());
-            let take = self
-                .fragment_size
-                .min(max)
-                .min(error_limit - self.offset)
-                .min(self.bytes.len() - self.offset);
-            let start = self.offset;
-            self.offset += take;
-            Poll::Ready(Ok(ShardChunkRead::Chunk(self.bytes.slice(start..start + take))))
-        }
-    }
-
-    struct InvalidChunkSource {
-        mode: InvalidChunkMode,
-    }
-
-    #[derive(Clone, Copy)]
-    enum InvalidChunkMode {
-        Empty,
-        Oversized,
-        UnsupportedAfterChunk,
-        Unsupported,
-    }
-
-    impl AsyncRead for InvalidChunkSource {
-        fn poll_read(self: Pin<&mut Self>, _cx: &mut Context<'_>, _buf: &mut ReadBuf<'_>) -> Poll<io::Result<()>> {
-            Poll::Ready(Err(io::Error::other("invalid source must use chunk handoff")))
-        }
-    }
-
-    impl ShardSource for InvalidChunkSource {
-        fn poll_read_chunk(mut self: Pin<&mut Self>, _cx: &mut Context<'_>, max: usize) -> Poll<io::Result<ShardChunkRead>> {
-            match self.mode {
-                InvalidChunkMode::Empty => Poll::Ready(Ok(ShardChunkRead::Chunk(Bytes::new()))),
-                InvalidChunkMode::Oversized => Poll::Ready(Ok(ShardChunkRead::Chunk(Bytes::from(vec![0; max + 1])))),
-                InvalidChunkMode::UnsupportedAfterChunk => {
-                    self.mode = InvalidChunkMode::Unsupported;
-                    Poll::Ready(Ok(ShardChunkRead::Chunk(Bytes::from_static(b"x"))))
-                }
-                InvalidChunkMode::Unsupported => Poll::Ready(Ok(ShardChunkRead::Unsupported)),
-            }
-        }
-    }
-
-    struct ScratchReuseSource {
-        block: Option<Bytes>,
-        saw_reused_scratch: bool,
-    }
-
-    impl AsyncRead for ScratchReuseSource {
-        fn poll_read(mut self: Pin<&mut Self>, _cx: &mut Context<'_>, buf: &mut ReadBuf<'_>) -> Poll<io::Result<()>> {
-            let Some(block) = self.block.take() else {
-                return Poll::Ready(Ok(()));
-            };
-            self.saw_reused_scratch = buf.initialize_unfilled()[..block.len()].iter().all(|byte| *byte == 0xa5);
-            buf.put_slice(&block);
-            Poll::Ready(Ok(()))
-        }
-    }
-
-    impl ShardSource for ScratchReuseSource {}
+    use tokio::io::{AsyncWrite, AsyncWriteExt};

    #[derive(Default)]
    struct VectoredCountingWriter {
@@ -1740,70 +1446,6 @@ mod tests {
        assert!(out.is_empty(), "corrupt bytes must never reach the caller's buffer");
    }

-    #[tokio::test]
-    async fn chunked_handoff_verifies_data_split_across_hash_boundaries() {
-        const SHARD: usize = 4096;
-        let algo = HashAlgorithm::HighwayHash256S;
-        let data: Vec<u8> = (0..SHARD).map(|index| (index % 251) as u8).collect();
-        let mut encoded = Vec::new();
-        BitrotWriter::new(&mut encoded, SHARD, algo.clone())
-            .write(&data)
-            .await
-            .expect("write shard");
-
-        let mut output = Vec::with_capacity(SHARD);
-        BitrotReader::new(FragmentedSource::new(encoded, &[3, 11, 19, 37, 128]), SHARD, algo, false)
-            .read_appending(&mut output, SHARD)
-            .await
-            .expect("fragmented shard must verify");
-
-        assert_eq!(output, data);
-    }
-
-    #[tokio::test]
-    async fn chunked_handoff_never_appends_a_corrupt_shard() {
-        const SHARD: usize = 4096;
-        let algo = HashAlgorithm::HighwayHash256S;
-        let mut encoded = Vec::new();
-        BitrotWriter::new(&mut encoded, SHARD, algo.clone())
-            .write(&vec![9u8; SHARD])
-            .await
-            .expect("write shard");
-        let last = encoded.len() - 1;
-        encoded[last] ^= 0xff;
-
-        let mut output = Vec::with_capacity(SHARD);
-        let err = BitrotReader::new(FragmentedSource::new(encoded, &[7, 17, 31]), SHARD, algo, false)
-            .read_appending(&mut output, SHARD)
-            .await
-            .expect_err("corrupt fragmented shard must fail");
-
-        assert_eq!(err.kind(), io::ErrorKind::InvalidData);
-        assert!(output.is_empty());
-    }
-
-    #[tokio::test]
-    async fn chunked_handoff_does_not_hash_when_verification_is_skipped() {
-        const SHARD: usize = 4096;
-        let algo = HashAlgorithm::HighwayHash256S;
-        let mut encoded = Vec::new();
-        BitrotWriter::new(&mut encoded, SHARD, algo.clone())
-            .write(&vec![9u8; SHARD])
-            .await
-            .expect("write shard");
-        encoded[0] ^= 0xff;
-
-        let mut output = Vec::with_capacity(SHARD);
-        let mut reader = BitrotReader::new(FragmentedSource::new(encoded, &[7, 17, 31]), SHARD, algo, true);
-        reader
-            .read_appending(&mut output, SHARD)
-            .await
-            .expect("skipped verification must accept fragmented shard bytes");
-
-        assert_eq!(reader.last_verify_duration(), Duration::ZERO);
-        assert_eq!(output, vec![9u8; SHARD]);
-    }
-
    #[tokio::test]
    async fn read_appending_rejects_a_want_larger_than_the_shard() {
        let algo = HashAlgorithm::HighwayHash256;
@@ -1855,21 +1497,10 @@ mod tests {

        // Equivalence: same bytes out of both paths.
        let mut via_mem: Vec<u8> = Vec::with_capacity(SHARD);
-        let mut memory_reader = BitrotReader::new(Cursor::new(Bytes::from(encoded.clone())), SHARD, algo.clone(), false);
-        memory_reader
+        BitrotReader::new(Cursor::new(Bytes::from(encoded.clone())), SHARD, algo.clone(), false)
            .read_appending(&mut via_mem, SHARD)
            .await
            .expect("in-memory read");
-        assert_eq!(
-            memory_reader.chunks.capacity(),
-            0,
-            "the synchronous fast path must not allocate chunk storage"
-        );
-        assert_eq!(
-            memory_reader.buf.capacity(),
-            0,
-            "the synchronous fast path must not allocate scratch storage"
-        );

        let mut via_stream: Vec<u8> = Vec::with_capacity(SHARD);
        BitrotReader::new(Cursor::new(encoded), SHARD, algo, false)
@@ -1906,152 +1537,4 @@ mod tests {
        assert_eq!(err.kind(), std::io::ErrorKind::InvalidData);
        assert!(out.is_empty(), "corrupt bytes must never reach the caller's buffer");
    }
-
-    #[tokio::test]
-    async fn streaming_fallback_reuses_initialized_scratch() {
-        const SHARD: usize = 4096;
-        let algo = HashAlgorithm::HighwayHash256S;
-        let data = vec![7u8; SHARD];
-        let encoded = encode_one_block(&data, SHARD, algo.clone()).await;
-        let source = ScratchReuseSource {
-            block: Some(Bytes::copy_from_slice(&encoded)),
-            saw_reused_scratch: false,
-        };
-        let mut reader = BitrotReader::new(source, SHARD, algo, false);
-        reader.buf = vec![0xa5; encoded.len()];
-        let mut output = Vec::new();
-
-        reader
-            .read_appending(&mut output, SHARD)
-            .await
-            .expect("streaming fallback should verify");
-
-        assert!(reader.inner.saw_reused_scratch, "capability probing must not clear reusable scratch");
-        assert_eq!(output, data);
-    }
-
-    #[tokio::test]
-    async fn chunked_handoff_bounds_production_sized_one_byte_fragments() {
-        const SHARD: usize = 1024 * 1024 / 4;
-        let algo = HashAlgorithm::HighwayHash256S;
-        let data: Vec<u8> = (0..SHARD).map(|index| (index % 251) as u8).collect();
-        let encoded = encode_one_block(&data, SHARD, algo.clone()).await;
-        let encoded_len = encoded.len();
-        let mut reader = BitrotReader::new(GeneratedChunkSource::new(encoded, 1), SHARD, algo, false);
-        let mut output = Vec::with_capacity(SHARD);
-
-        reader
-            .read_appending(&mut output, SHARD)
-            .await
-            .expect("one-byte fragments should verify with bounded retained state");
-
-        assert_eq!(output, data);
-        assert_eq!(reader.chunks.len(), MAX_RETAINED_CHUNKS_PER_BLOCK);
-        assert!(reader.chunks.capacity() <= MAX_RETAINED_CHUNKS_PER_BLOCK);
-        assert_eq!(reader.buf.len(), encoded_len - MAX_RETAINED_CHUNKS_PER_BLOCK);
-    }
-
-    #[tokio::test]
-    async fn chunked_handoff_keeps_sixty_four_frames_zero_copy_and_respects_poll_budget() {
-        const SHARD: usize = 1024 * 1024;
-        const FRAME: usize = 16 * 1024;
-        let algo = HashAlgorithm::HighwayHash256S;
-
-        let small_data = vec![3u8; 4096];
-        let small_encoded = encode_one_block(&small_data, 4096, algo.clone()).await;
-        let mut exact_reader =
-            BitrotReader::new(FragmentedSource::new(small_encoded.clone(), &[1; 63]), 4096, algo.clone(), false);
-        let mut exact_output = Vec::new();
-        exact_reader
-            .read_appending(&mut exact_output, 4096)
-            .await
-            .expect("exactly sixty-four frames should verify");
-        assert_eq!(exact_output, small_data);
-        assert_eq!(exact_reader.chunks.len(), MAX_RETAINED_CHUNKS_PER_BLOCK);
-        assert!(exact_reader.buf.is_empty(), "the threshold itself must remain zero-copy");
-
-        let mut yielded_reader = BitrotReader::new(FragmentedSource::new(small_encoded, &[1; 65]), 4096, algo.clone(), false);
-        let mut yielded_output = Vec::new();
-        let mut yielded_read = Box::pin(yielded_reader.read_appending(&mut yielded_output, 4096));
-        let mut cx = Context::from_waker(std::task::Waker::noop());
-        assert!(std::future::Future::poll(yielded_read.as_mut(), &mut cx).is_pending());
-        assert!(matches!(std::future::Future::poll(yielded_read.as_mut(), &mut cx), Poll::Ready(Ok(4096))));
-        drop(yielded_read);
-        assert_eq!(yielded_output, small_data);
-
-        let data = vec![7u8; SHARD];
-        let encoded = encode_one_block(&data, SHARD, algo.clone()).await;
-        let mut reader = BitrotReader::new(FragmentedSource::new(encoded, &[FRAME; 64]), SHARD, algo, false);
-        let mut output = Vec::with_capacity(SHARD);
-        let mut read = Box::pin(reader.read_appending(&mut output, SHARD));
-        assert!(
-            matches!(std::future::Future::poll(read.as_mut(), &mut cx), Poll::Ready(Ok(SHARD))),
-            "sixty-five normal HTTP frames should complete without a cooperative yield"
-        );
-        drop(read);
-
-        assert_eq!(output, data);
-        assert_eq!(reader.chunks.len(), MAX_RETAINED_CHUNKS_PER_BLOCK);
-        assert_eq!(reader.buf.len(), HashAlgorithm::HighwayHash256S.size());
-    }
-
-    #[tokio::test]
-    async fn chunked_tail_failures_preserve_errors_and_output() {
-        const SHARD: usize = 4096;
-        let algo = HashAlgorithm::HighwayHash256S;
-        let data = vec![7u8; SHARD];
-        let encoded = encode_one_block(&data, SHARD, algo.clone()).await;
-        let sentinel = vec![1u8, 2, 3];
-
-        let mut short_output = sentinel.clone();
-        let short_err = BitrotReader::new(GeneratedChunkSource::new(encoded[..100].to_vec(), 1), SHARD, algo.clone(), false)
-            .read_appending(&mut short_output, SHARD)
-            .await
-            .expect_err("EOF after the retention threshold must stay a short read");
-        assert_eq!(short_err.kind(), io::ErrorKind::UnexpectedEof);
-        assert_eq!(short_output, sentinel);
-
-        let mut corrupt = encoded.clone();
-        let last = corrupt.len() - 1;
-        corrupt[last] ^= 0xff;
-        let mut corrupt_output = sentinel.clone();
-        let corrupt_err = BitrotReader::new(GeneratedChunkSource::new(corrupt, 1), SHARD, algo.clone(), false)
-            .read_appending(&mut corrupt_output, SHARD)
-            .await
-            .expect_err("corrupt coalesced tail must fail verification");
-        assert_eq!(corrupt_err.kind(), io::ErrorKind::InvalidData);
-        assert_eq!(corrupt_output, sentinel);
-
-        let mut failed_output = sentinel.clone();
-        let body_err = BitrotReader::new(GeneratedChunkSource::failing(encoded, 1, 65), SHARD, algo, false)
-            .read_appending(&mut failed_output, SHARD)
-            .await
-            .expect_err("a terminal body error must not become EOF");
-        let source = body_err
-            .get_ref()
-            .and_then(|source| source.downcast_ref::<rustfs_rio::InternodeHttpError>())
-            .expect("body error should retain internode classification");
-        assert_eq!(source.kind(), rustfs_rio::InternodeHttpErrorKind::BodyStreamAborted);
-        assert_eq!(failed_output, sentinel);
-    }
-
-    #[tokio::test]
-    async fn chunked_handoff_rejects_invalid_source_contracts() {
-        const SHARD: usize = 64;
-        for mode in [
-            InvalidChunkMode::Empty,
-            InvalidChunkMode::Oversized,
-            InvalidChunkMode::UnsupportedAfterChunk,
-        ] {
-            let source = InvalidChunkSource { mode };
-            let mut output = vec![9u8];
-            let err = BitrotReader::new(source, SHARD, HashAlgorithm::HighwayHash256S, false)
-                .read_appending(&mut output, SHARD)
-                .await
-                .expect_err("invalid chunk contracts must fail closed");
-
-            assert_eq!(err.kind(), io::ErrorKind::InvalidData);
-            assert_eq!(output, vec![9u8]);
-        }
-    }
 }
@@ -25,9 +25,7 @@ use crate::disk::error_reduce::reduce_errs;
 use crate::erasure::codec::workspace::ShardBufferPool;
 use crate::erasure::coding::{BitrotReader, Erasure};
 use crate::io_support::bitrot::DeferredReaderStripeHandle;
-use crate::set_disk::shard_source::{
-    INLINE_SHARD_SLOTS, ShardBuffers, ShardErrors, ShardReadCost, ShardStripeSource, StripeReadState,
-};
+use crate::set_disk::shard_source::{ShardReadCost, ShardStripeSource, StripeReadState};
 use futures::FutureExt;
 use futures::stream::{FuturesUnordered, StreamExt};
 use pin_project_lite::pin_project;
@@ -43,6 +41,9 @@ use tracing::{debug, error, warn};

 type ShardReadFuture<'a> = Pin<Box<dyn Future<Output = (usize, ShardReadCost, Result<Vec<u8>, Error>, bool)> + Send + 'a>>;

+const INLINE_SHARD_SLOTS: usize = 32;
+type ShardBuffers = SmallVec<[Option<Vec<u8>>; INLINE_SHARD_SLOTS]>;
+type ShardErrors = SmallVec<[Option<Error>; INLINE_SHARD_SLOTS]>;
 type ShardIndexes = SmallVec<[usize; INLINE_SHARD_SLOTS]>;
 type ActiveReaders = SmallVec<[bool; INLINE_SHARD_SLOTS]>;

@@ -213,7 +214,6 @@ fn shard_read_launch_rank(cost: ShardReadCost) -> u8 {
    }
 }

-#[allow(dead_code, reason = "launch ordering asserted by this file's tests (backlog#1823)")]
 fn shard_read_launch_order(read_costs: &[ShardReadCost], num_readers: usize, locality_preference_enabled: bool) -> Vec<usize> {
    let mut order: Vec<usize> = (0..num_readers).collect();
    if locality_preference_enabled {
@@ -392,7 +392,6 @@ pub(crate) struct ParallelReader<R> {
    // Request-scoped shard buffers keyed by shard index. Keeping ownership in
    // `ParallelReader` avoids dropping unused parity/backup slot buffers between stripes.
    buffers: ShardBufferPool,
-    stripe_state: Option<Box<StripeReadState>>,
    // Lockstep-path state (verify_reconstruction == true). `engaged[i]` marks
    // readers that participate in each stripe read: all data slots from the
    // start, parity slots only once a data shard is missing/dead. Unengaged
@@ -409,10 +408,6 @@ where
    R: crate::erasure::coding::ShardSource,
 {
    // Readers should handle disk errors before being passed in, ensuring each reader reaches the available number of BitrotReaders
-    #[allow(
-        dead_code,
-        reason = "ParallelReader constructor used only by this file's tests (backlog#1823)"
-    )]
    pub fn new(readers: Vec<Option<BitrotReader<R>>>, e: Erasure, offset: usize, total_length: usize) -> Self {
        Self::new_with_metrics_path_read_timeout_and_reconstruction_verification(
            readers,
@@ -425,7 +420,6 @@ where
        )
    }

-    #[allow(dead_code, reason = "constructor used only by this file's tests (backlog#1823)")]
    pub fn new_with_metrics_path(
        readers: Vec<Option<BitrotReader<R>>>,
        e: Erasure,
@@ -444,7 +438,6 @@ where
        )
    }

-    #[allow(dead_code, reason = "constructor used only by this file's tests (backlog#1823)")]
    pub fn new_with_metrics_path_and_read_costs(
        readers: Vec<Option<BitrotReader<R>>>,
        e: Erasure,
@@ -521,7 +514,6 @@ where
        )
    }

-    #[allow(dead_code, reason = "constructor used only by this file's tests (backlog#1823)")]
    fn new_with_read_timeout(
        readers: Vec<Option<BitrotReader<R>>>,
        e: Erasure,
@@ -604,7 +596,6 @@ where
            verify_reconstruction,
            locality_preference_enabled: get_shard_locality_preference_enabled(),
            buffers: ShardBufferPool::new(e.data_shards + e.parity_shards),
-            stripe_state: None,
            engaged,
            deferred_handles: Vec::new(),
            stripe_index: 0,
@@ -709,12 +700,6 @@ where
 {
    #[hotpath::measure(impl_type = "ParallelReader")]
    pub async fn read(&mut self) -> StripeReadOutput {
-        let mut state = StripeReadState::with_slot_count(self.readers.len(), self.data_shards);
-        self.read_into_state(&mut state).await;
-        state.into_parts()
-    }
-
-    async fn read_into_state(&mut self, state: &mut StripeReadState) {
        // On the reconstruction-verifying GET path, read every live shard reader
        // in lockstep so all readers advance one block per stripe and stay
        // mutually aligned. The adaptive data-first path below only reads
@@ -724,14 +709,12 @@ where
        // than the data shards, producing "inconsistent read source shards" and
        // truncating large-object GETs under concurrency (backlog#832).
        if self.verify_reconstruction {
-            self.read_lockstep(state).await;
-            return;
+            return self.read_lockstep().await;
        }
        // if self.readers.len() != self.total_shards {
        //     return Err(io::Error::new(ErrorKind::InvalidInput, "Invalid number of readers"));
        // }
        let num_readers = self.readers.len();
-        state.reset(num_readers, self.data_shards);

        let shard_size = if self.offset + self.shard_size > self.shard_file_size {
            self.shard_file_size - self.offset
@@ -740,7 +723,7 @@ where
        };

        if shard_size == 0 {
-            return;
+            return (smallvec![None; num_readers], smallvec![None; num_readers]);
        }

        // Advance to the next stripe so the following read() computes the correct
@@ -751,7 +734,8 @@ where
        // is only read above to derive `shard_size`, so advancing here is safe.
        self.offset += shard_size;

-        let (shards, errs) = state.parts_mut();
+        let mut shards: ShardBuffers = smallvec![None; num_readers];
+        let mut errs: ShardErrors = smallvec![None; num_readers];
        let read_costs = self.read_costs.as_slice();
        let locality_preference_enabled = self.locality_preference_enabled;
        let low_cost_available = self
@@ -898,8 +882,8 @@ where
                }

                let result_is_err = record_shard_read_result(
-                    shards,
-                    errs,
+                    &mut shards,
+                    &mut errs,
                    &mut retire_readers,
                    &mut success,
                    &mut successful_costs,
@@ -960,8 +944,8 @@ where
                    active_readers[i] = false;
                    completed += 1;
                    if record_shard_read_result(
-                        shards,
-                        errs,
+                        &mut shards,
+                        &mut errs,
                        &mut retire_readers,
                        &mut success,
                        &mut successful_costs,
@@ -973,7 +957,7 @@ where
                        failed += 1;
                    }
                }
-                retire_abandoned_readers(errs, &mut retire_readers, &active_readers);
+                retire_abandoned_readers(&mut errs, &mut retire_readers, &active_readers);
            }

            if let Some(path) = self.metrics_path {
@@ -1017,6 +1001,8 @@ where
        for i in retire_readers {
            self.readers[i] = None;
        }
+
+        (shards, errs)
    }

    /// Lockstep stripe read for the reconstruction-verifying GET path.
@@ -1044,18 +1030,18 @@ where
    /// stripe would reintroduce the desync. A parity reader that cannot be
    /// realigned (no pending deferred handle) is likewise retired instead of
    /// being read out of position.
-    async fn read_lockstep(&mut self, state: &mut StripeReadState) {
+    async fn read_lockstep(&mut self) -> StripeReadOutput {
        let num_readers = self.readers.len();
-        state.reset(num_readers, self.data_shards);
        let shard_size = if self.offset + self.shard_size > self.shard_file_size {
            self.shard_file_size - self.offset
        } else {
            self.shard_size
        };

-        let (shards, errs) = state.parts_mut();
+        let mut shards: ShardBuffers = smallvec![None; num_readers];
+        let mut errs: ShardErrors = smallvec![None; num_readers];
        if shard_size == 0 {
-            return;
+            return (shards, errs);
        }

        // Advance to the next stripe (see the matching note in `read`); the
@@ -1293,6 +1279,8 @@ where
        for i in retire_readers {
            self.readers[i] = None;
        }
+
+        (shards, errs)
    }

    /// Attempt to bring an as-yet-unread parity reader into the lockstep read
@@ -1338,6 +1326,10 @@ where
            }
        }
    }
+
+    pub fn can_decode(&self, shards: &[Option<Vec<u8>>]) -> bool {
+        shards.iter().filter(|s| s.is_some()).count() >= self.data_shards
+    }
 }

 #[async_trait::async_trait]
@@ -1345,20 +1337,10 @@ impl<R> ShardStripeSource for ParallelReader<R>
 where
    R: crate::erasure::coding::ShardSource,
 {
-    async fn read_next_stripe(&mut self) -> Box<StripeReadState> {
-        let mut state = self
-            .stripe_state
-            .take()
-            .unwrap_or_else(|| Box::new(StripeReadState::with_slot_count(self.readers.len(), self.data_shards)));
-        self.read_into_state(&mut state).await;
-        state
-    }
-
-    fn recycle_stripe(&mut self, mut state: Box<StripeReadState>) {
-        self.recycle_shards(state.shards_mut());
-        state.reset(0, self.data_shards);
-        debug_assert!(self.stripe_state.is_none(), "a stripe cannot be recycled twice");
-        self.stripe_state = Some(state);
+    async fn read_next_stripe(&mut self) -> StripeReadState {
+        let read_quorum = self.data_shards;
+        let (shards, errors) = ParallelReader::read(self).await;
+        StripeReadState::from_parts_with_read_costs(shards, errors, &self.read_costs, read_quorum)
    }
 }

@@ -1543,7 +1525,6 @@ impl Erasure {
            .await
    }

-    #[allow(dead_code, reason = "read-cost decode path asserted by this file's tests (backlog#1823)")]
    pub(crate) async fn decode_with_read_costs<W, R>(
        &self,
        writer: &mut W,
@@ -1614,9 +1595,9 @@ impl Erasure {
            *ret_err = Some(err.into());
        }

-        // Shard-availability check, written out here rather than called on the
-        // reader so this helper does not need to borrow it, leaving the reader
-        // free for the concurrent next-stripe read under prefetch.
+        // Equivalent to `ParallelReader::can_decode`; inlined so this helper does
+        // not need to borrow the reader, leaving the reader free for the
+        // concurrent next-stripe read under prefetch.
        let available_shards = shards.iter().filter(|shard| shard.is_some()).count();
        if available_shards < self.data_shards {
            let reason = GetObjectFailureReason::ReadQuorum;
@@ -1991,18 +1972,13 @@ mod tests {
    type BoxedShardReader = crate::io_support::bitrot::ShardReader;

    #[test]
-    fn parallel_reader_keeps_stripe_scratch_out_of_line() {
-        eprintln!(
-            "parallel_reader={} stripe_state={} cached_state={}",
-            std::mem::size_of::<ParallelReader<Cursor<Vec<u8>>>>(),
-            std::mem::size_of::<StripeReadState>(),
-            std::mem::size_of::<Option<Box<StripeReadState>>>()
-        );
-        assert_eq!(
-            std::mem::size_of::<Option<Box<StripeReadState>>>(),
-            std::mem::size_of::<usize>(),
-            "the request-scoped cache must remain pointer-sized",
-        );
+    fn shard_scratch_stays_inline_through_the_common_limit_and_spills_safely() {
+        let inline: ShardBuffers = smallvec![None; INLINE_SHARD_SLOTS];
+        assert!(!inline.spilled(), "the common shard-count boundary must not allocate");
+
+        let spilled: ShardBuffers = smallvec![None; INLINE_SHARD_SLOTS + 1];
+        assert!(spilled.spilled(), "larger supported shard counts must fall back to the heap");
+        assert_eq!(spilled.len(), INLINE_SHARD_SLOTS + 1);
    }

    #[tokio::test]
@@ -2021,62 +1997,6 @@ mod tests {
        assert_eq!(errors.len(), TOTAL_SHARDS);
    }

-    #[tokio::test]
-    async fn codec_reader_reuses_inline_and_spilled_stripe_scratch_between_reads() {
-        for total_shards in [INLINE_SHARD_SLOTS, INLINE_SHARD_SLOTS + 1] {
-            let data_shards = total_shards - 1;
-            let readers = std::iter::repeat_with(|| None).take(total_shards).collect();
-            let erasure = Erasure::new(data_shards, 1, data_shards * 2);
-            let mut reader: ParallelReader<Cursor<Vec<u8>>> = ParallelReader::new(readers, erasure, 0, data_shards * 2);
-
-            let first = ShardStripeSource::read_next_stripe(&mut reader).await;
-            let first_state = (&*first) as *const StripeReadState;
-            let first_storage = first.scratch_storage();
-            assert_eq!(first_storage.2, total_shards > INLINE_SHARD_SLOTS);
-            assert_eq!(first_storage.3, total_shards > INLINE_SHARD_SLOTS);
-            ShardStripeSource::recycle_stripe(&mut reader, first);
-
-            let second = ShardStripeSource::read_next_stripe(&mut reader).await;
-            let second_storage = second.scratch_storage();
-
-            assert_eq!(
-                (&*second) as *const StripeReadState,
-                first_state,
-                "the request-scoped state must be reused"
-            );
-            assert_eq!(second_storage.0, first_storage.0, "shard slots must reuse their allocation");
-            assert_eq!(second_storage.1, first_storage.1, "error slots must reuse their allocation");
-            assert_eq!(second.into_parts().0.len(), total_shards);
-        }
-    }
-
-    #[tokio::test]
-    async fn codec_reader_returns_shard_allocations_to_the_request_pool() {
-        const SHARD_SIZE: usize = 16;
-        let hash_algo = HashAlgorithm::None;
-        let readers = vec![Some(create_reader(SHARD_SIZE, 2, 0x5a, &hash_algo, false).await)];
-        let erasure = Erasure::new(1, 0, SHARD_SIZE);
-        let mut reader = ParallelReader::new(readers, erasure, 0, SHARD_SIZE * 2);
-
-        let first = ShardStripeSource::read_next_stripe(&mut reader).await;
-        let first_allocation = first
-            .shard_allocation(0)
-            .expect("the first stripe should own its shard allocation");
-        ShardStripeSource::recycle_stripe(&mut reader, first);
-        assert_eq!(
-            reader.buffers.stored_allocation(0),
-            Some(first_allocation),
-            "recycling a stripe must return its shard allocation to the request pool"
-        );
-
-        let second = ShardStripeSource::read_next_stripe(&mut reader).await;
-        assert_eq!(
-            second.shard_allocation(0),
-            Some(first_allocation),
-            "the next stripe must reuse the pooled shard allocation"
-        );
-    }
-
    /// Counts the raw bytes pulled from a shard stream, to prove which shards
    /// a decode path actually touches (backlog#923 call-count evidence).
    struct CountingShardReader {
@@ -65,7 +65,7 @@ enum FillPolicy {
 }

 impl FillPolicy {
-    fn load() -> Self {
+    fn from_env() -> Self {
        match rustfs_utils::get_env_usize(
            ENV_RUSTFS_GET_CODEC_STREAMING_MAX_INFLIGHT,
            DEFAULT_RUSTFS_GET_CODEC_STREAMING_MAX_INFLIGHT,
@@ -75,22 +75,6 @@ impl FillPolicy {
        }
    }

-    fn from_env() -> Self {
-        #[cfg(test)]
-        {
-            Self::load()
-        }
-        #[cfg(not(test))]
-        {
-            Self::cached_core(Self::load)
-        }
-    }
-
-    fn cached_core(load: impl FnOnce() -> Self) -> Self {
-        static CACHED: std::sync::OnceLock<FillPolicy> = std::sync::OnceLock::new();
-        *CACHED.get_or_init(load)
-    }
-
    const fn max_inflight(self) -> usize {
        match self {
            Self::SingleInFlight => 1,
@@ -138,10 +122,6 @@ where
    S: ShardStripeSource + Send + 'static,
    E: ErasureDecodeEngine + Clone + Send + Sync + 'static,
 {
-    #[allow(
-        dead_code,
-        reason = "default-metrics-path constructor used only by this file's tests (backlog#1823)"
-    )]
    pub(crate) fn new(source: S, engine: E, total_length: usize) -> io::Result<Self> {
        Self::new_with_metrics_path(source, engine, total_length, GET_OBJECT_PATH_CODEC_STREAMING)
    }
@@ -499,30 +479,22 @@ where
    let mut deferred_error = None;
    let fill_stage_start = get_stage_timer_if_enabled(stage_metrics_enabled);
    let stripe_read_stage_start = get_stage_timer_if_enabled(stage_metrics_enabled);
-    let mut state = source.read_next_stripe().await;
+    let state = source.read_next_stripe().await;
    record_get_stage_duration_if_enabled(metrics_path, GET_STAGE_STRIPE_READ, stripe_read_stage_start);
    let decode_stage_start = get_stage_timer_if_enabled(stage_metrics_enabled);
    let mut output_buf = reusable_buffers.pop().unwrap_or_default();
-    let result = match decode_stripe_into(
-        metrics_path,
-        stage_metrics_enabled,
-        engine,
-        workspace,
-        &mut state,
-        remaining,
-        &mut output_buf,
-    ) {
-        Ok(true) => Ok(Some(output_buf)),
-        Ok(false) => {
-            reusable_buffers.push(output_buf);
-            Ok(None)
-        }
-        Err(err) => {
-            reusable_buffers.push(output_buf);
-            Err(err)
-        }
-    };
-    source.recycle_stripe(state);
+    let result =
+        match decode_stripe_into(metrics_path, stage_metrics_enabled, engine, workspace, state, remaining, &mut output_buf) {
+            Ok(true) => Ok(Some(output_buf)),
+            Ok(false) => {
+                reusable_buffers.push(output_buf);
+                Ok(None)
+            }
+            Err(err) => {
+                reusable_buffers.push(output_buf);
+                Err(err)
+            }
+        };
    record_get_stage_duration_if_enabled(metrics_path, GET_STAGE_DECODE, decode_stage_start);
    if let Ok(Some(first_buf)) = result.as_ref() {
        let mut remaining_after_first = remaining.saturating_sub(first_buf.len());
@@ -531,7 +503,7 @@ where
                break;
            }
            let stripe_read_stage_start = get_stage_timer_if_enabled(stage_metrics_enabled);
-            let mut state = source.read_next_stripe().await;
+            let state = source.read_next_stripe().await;
            record_get_stage_duration_if_enabled(metrics_path, GET_STAGE_STRIPE_READ, stripe_read_stage_start);
            let decode_stage_start = get_stage_timer_if_enabled(stage_metrics_enabled);
            let mut queued_buf = reusable_buffers.pop().unwrap_or_default();
@@ -540,11 +512,10 @@ where
                stage_metrics_enabled,
                engine,
                workspace,
-                &mut state,
+                state,
                remaining_after_first,
                &mut queued_buf,
            );
-            source.recycle_stripe(state);
            record_get_stage_duration_if_enabled(metrics_path, GET_STAGE_DECODE, decode_stage_start);
            match queued_result {
                Ok(true) => {
@@ -683,10 +654,6 @@ pub(crate) struct SyncErasureDecodeReader<R> {
 }

 impl<R> SyncErasureDecodeReader<R> {
-    #[allow(
-        dead_code,
-        reason = "default-metrics-path constructor used only by this file's tests (backlog#1823)"
-    )]
    pub(crate) fn new(inner: R) -> Self {
        Self::new_with_metrics_path(inner, GET_OBJECT_PATH_CODEC_STREAMING)
    }
@@ -750,7 +717,7 @@ fn decode_stripe_into<E>(
    stage_metrics_enabled: bool,
    engine: &E,
    workspace: &mut E::Workspace,
-    state: &mut StripeReadState,
+    state: StripeReadState,
    remaining: usize,
    output: &mut Vec<u8>,
 ) -> io::Result<bool>
@@ -758,7 +725,7 @@ where
    E: ErasureDecodeEngine,
 {
    output.clear();
-    if state.is_empty() {
+    if state.slots().is_empty() {
        return Ok(false);
    }
    if !state.can_decode() {
@@ -774,12 +741,13 @@ where
        );
        record_get_stage_duration_if_enabled(metrics_path, GET_STAGE_RECONSTRUCT, reconstruct_stage_start);
        let emit_stage_start = get_stage_timer_if_enabled(stage_metrics_enabled);
-        emit_data_shards_into(state, engine.data_shards(), engine.block_size(), remaining, output)?;
+        emit_data_shards_into(&state, engine.data_shards(), engine.block_size(), remaining, output)?;
        record_get_stage_duration_if_enabled(metrics_path, GET_STAGE_EMIT, emit_stage_start);
        return Ok(true);
    }

-    let reconstruct_outcome = match engine.reconstruct_into(state.shards_mut(), workspace) {
+    let (mut shards, _errs) = state.into_parts();
+    let reconstruct_outcome = match engine.reconstruct_into(&mut shards, workspace) {
        Ok(outcome) => outcome,
        Err(err) => {
            record_get_stage_duration_if_enabled(metrics_path, GET_STAGE_RECONSTRUCT, reconstruct_stage_start);
@@ -789,7 +757,7 @@ where
    rustfs_io_metrics::record_get_object_reconstruct_outcome(metrics_path, engine.engine_name(), reconstruct_outcome);
    record_get_stage_duration_if_enabled(metrics_path, GET_STAGE_RECONSTRUCT, reconstruct_stage_start);

-    if state.shards_mut().len() < engine.data_shards() {
+    if shards.len() < engine.data_shards() {
        return Err(io::Error::new(
            ErrorKind::UnexpectedEof,
            "decoded stripe has fewer shards than data shard count",
@@ -798,7 +766,7 @@ where

    let emit_stage_start = get_stage_timer_if_enabled(stage_metrics_enabled);
    reserve_output_capacity(output, engine.block_size().min(remaining));
-    for shard in state.shards_mut().iter().take(engine.data_shards()) {
+    for shard in shards.iter().take(engine.data_shards()) {
        if output.len() >= remaining {
            break;
        }
@@ -813,7 +781,6 @@ where
    Ok(true)
 }

-#[allow(dead_code, reason = "shard emission asserted by this file's tests (backlog#1823)")]
 fn emit_data_shards(state: &StripeReadState, data_shards: usize, block_size: usize, remaining: usize) -> io::Result<Vec<u8>> {
    let mut output = Vec::new();
    emit_data_shards_into(state, data_shards, block_size, remaining, &mut output)?;
@@ -839,7 +806,10 @@ fn emit_data_shards_into(
        if output.len() >= remaining {
            break;
        }
-        let Some(shard) = state.data_bytes(index) else {
+        let Some(slot) = state.slot_by_index(index) else {
+            return Err(io::Error::new(ErrorKind::UnexpectedEof, "decoded stripe is missing a data shard"));
+        };
+        let Some(shard) = slot.data_bytes() else {
            return Err(io::Error::new(ErrorKind::UnexpectedEof, "decoded stripe is missing a data shard"));
        };
        let copy_len = shard.len().min(remaining - output.len());
@@ -856,7 +826,7 @@ mod tests {
    };
    use crate::erasure::coding::decode::ParallelReader;
    use crate::erasure::coding::{BitrotReader, BitrotWriter, Erasure};
-    use crate::set_disk::shard_source::StripeReadState;
+    use crate::set_disk::shard_source::{ShardSlot, StripeReadState};
    use rustfs_utils::HashAlgorithm;
    use std::collections::VecDeque;
    use std::future::{pending, poll_fn};
@@ -875,13 +845,6 @@ mod tests {
        read_count: Option<Arc<AtomicUsize>>,
    }

-    struct RecordingStripeSource {
-        stripes: VecDeque<StripeReadState>,
-        read_quorum: usize,
-        reads: usize,
-        recycles: usize,
-    }
-
    struct BlockingSource {
        started: Arc<Notify>,
        dropped: Arc<AtomicUsize>,
@@ -936,43 +899,25 @@ mod tests {

    #[async_trait::async_trait]
    impl ShardStripeSource for VecStripeSource {
-        async fn read_next_stripe(&mut self) -> Box<StripeReadState> {
+        async fn read_next_stripe(&mut self) -> StripeReadState {
            if let Some(read_count) = &self.read_count {
                read_count.fetch_add(1, Ordering::SeqCst);
            }
-            Box::new(
-                self.stripes
-                    .pop_front()
-                    .unwrap_or_else(|| StripeReadState::from_parts(Vec::new(), Vec::new(), self.read_quorum)),
-            )
-        }
-    }
-
-    #[async_trait::async_trait]
-    impl ShardStripeSource for RecordingStripeSource {
-        async fn read_next_stripe(&mut self) -> Box<StripeReadState> {
-            self.reads += 1;
-            Box::new(
-                self.stripes
-                    .pop_front()
-                    .unwrap_or_else(|| StripeReadState::from_parts(Vec::new(), Vec::new(), self.read_quorum)),
-            )
-        }
-
-        fn recycle_stripe(&mut self, _state: Box<StripeReadState>) {
-            self.recycles += 1;
+            self.stripes
+                .pop_front()
+                .unwrap_or_else(|| StripeReadState::new(Vec::new(), self.read_quorum))
        }
    }

    #[async_trait::async_trait]
    impl ShardStripeSource for BlockingSource {
-        async fn read_next_stripe(&mut self) -> Box<StripeReadState> {
+        async fn read_next_stripe(&mut self) -> StripeReadState {
            let _guard = BlockingSourceDropGuard {
                dropped: Arc::clone(&self.dropped),
            };
            self.started.notify_one();
            pending::<()>().await;
-            Box::new(StripeReadState::from_parts(Vec::new(), Vec::new(), self.read_quorum))
+            StripeReadState::new(Vec::new(), self.read_quorum)
        }
    }

@@ -1145,23 +1090,6 @@ mod tests {
        });
    }

-    #[test]
-    fn fill_policy_production_cache_loads_once() {
-        use std::cell::Cell;
-
-        let loads = Cell::new(0);
-        for _ in 0..3 {
-            assert_eq!(
-                FillPolicy::cached_core(|| {
-                    loads.set(loads.get() + 1);
-                    FillPolicy::DualInFlight
-                }),
-                FillPolicy::DualInFlight
-            );
-        }
-        assert_eq!(loads.get(), 1, "the production fill policy must not re-read the environment per reader");
-    }
-
    #[test]
    fn erasure_decode_reader_rejects_invalid_engine_shape() {
        let source = VecStripeSource {
@@ -1761,10 +1689,7 @@ mod tests {
            .pop_front()
            .expect("first stripe should exist");
        let mut source = VecStripeSource {
-            stripes: VecDeque::from([
-                first_state,
-                StripeReadState::from_parts(Vec::new(), Vec::new(), erasure.data_shards),
-            ]),
+            stripes: VecDeque::from([first_state, StripeReadState::new(Vec::new(), erasure.data_shards)]),
            read_quorum: erasure.data_shards,
            read_count: None,
        };
@@ -1799,14 +1724,13 @@ mod tests {
            .stripes
            .pop_front()
            .expect("first stripe should exist");
-        let mut source = RecordingStripeSource {
+        let mut source = VecStripeSource {
            stripes: VecDeque::from([
                first_state,
-                StripeReadState::from_parts(vec![Some(vec![1])], Vec::new(), erasure.data_shards),
+                StripeReadState::new(vec![ShardSlot::data(0, vec![1])], erasure.data_shards),
            ]),
            read_quorum: erasure.data_shards,
-            reads: 0,
-            recycles: 0,
+            read_count: None,
        };
        let engine = LegacyEcDecodeEngine::new(erasure);
        let mut workspace = engine.prepare_workspace(4).expect("workspace should be prepared");
@@ -1832,8 +1756,6 @@ mod tests {
                .kind(),
            ErrorKind::Other
        );
-        assert_eq!(source.reads, 2, "the fill must read the primary and queued stripe");
-        assert_eq!(source.recycles, source.reads, "every completed stripe read must be recycled");
    }

    #[tokio::test]
@@ -1846,7 +1768,7 @@ mod tests {
                    .stripes
                    .pop_front()
                    .expect("first stripe should exist"),
-                StripeReadState::from_parts(Vec::new(), Vec::new(), erasure.data_shards),
+                StripeReadState::new(Vec::new(), erasure.data_shards),
            ]),
            read_quorum: erasure.data_shards,
            read_count: None,
@@ -2106,11 +2028,17 @@ mod tests {
    }

    #[test]
-    fn emit_data_shards_preserves_output_order() {
-        let state =
-            StripeReadState::from_parts(vec![Some(b"ab".to_vec()), Some(b"cd".to_vec()), Some(b"ef".to_vec())], Vec::new(), 2);
+    fn emit_data_shards_preserves_output_order_for_out_of_order_slots() {
+        let state = StripeReadState::new(
+            vec![
+                ShardSlot::data(1, b"cd".to_vec()),
+                ShardSlot::data(0, b"ab".to_vec()),
+                ShardSlot::data(2, b"ef".to_vec()),
+            ],
+            2,
+        );

-        let output = emit_data_shards(&state, 3, 6, 5).expect("data slots should emit by shard index");
+        let output = emit_data_shards(&state, 3, 6, 5).expect("out-of-order data slots should emit by shard index");

        assert_eq!(output, b"abcde");
    }
@@ -2123,27 +2051,27 @@ mod tests {
        };
        let mut workspace = engine.prepare_workspace(4).expect("workspace should be prepared");
        let mut output = Vec::with_capacity(1);
-        let mut short_state = StripeReadState::from_parts(vec![Some(vec![1, 2, 3, 4])], Vec::new(), 1);
+        let short_state = StripeReadState::new(vec![ShardSlot::data(0, vec![1, 2, 3, 4])], 1);

        let err = decode_stripe_into(
            GET_OBJECT_PATH_CODEC_STREAMING,
            false,
            &engine,
            &mut workspace,
-            &mut short_state,
+            short_state,
            8,
            &mut output,
        )
        .expect_err("decoded stripe shorter than data shard count must fail");
        assert_eq!(err.kind(), ErrorKind::UnexpectedEof);

-        let mut missing_state = StripeReadState::from_parts(vec![None, Some(vec![5, 6, 7, 8])], Vec::new(), 1);
+        let missing_state = StripeReadState::from_parts(vec![None, Some(vec![5, 6, 7, 8])], Vec::new(), 1);
        let err = decode_stripe_into(
            GET_OBJECT_PATH_CODEC_STREAMING,
            false,
            &engine,
            &mut workspace,
-            &mut missing_state,
+            missing_state,
            8,
            &mut output,
        )
@@ -2154,35 +2082,6 @@ mod tests {
        assert!(output.capacity() >= 32);
    }

-    #[test]
-    fn decode_stripe_reconstructs_in_place_without_replacing_slot_storage() {
-        let erasure = Erasure::new(2, 1, 8);
-        let engine = LegacyEcDecodeEngine::new(erasure.clone());
-        let mut workspace = engine.prepare_workspace(4).expect("workspace should be prepared");
-        let encoded = erasure.encode_data(b"abcdefgh").expect("test stripe should encode");
-        let mut shards = encoded.into_iter().map(|shard| Some(shard.to_vec())).collect::<Vec<_>>();
-        shards[0] = None;
-        let mut state = StripeReadState::from_parts(shards, vec![Some(DiskError::FileCorrupt)], 2);
-        let before = state.scratch_storage();
-        let mut output = Vec::new();
-
-        let decoded = decode_stripe_into(
-            GET_OBJECT_PATH_CODEC_STREAMING,
-            false,
-            &engine,
-            &mut workspace,
-            &mut state,
-            8,
-            &mut output,
-        )
-        .expect("degraded stripe should reconstruct");
-
-        assert!(decoded);
-        assert_eq!(output, b"abcdefgh");
-        assert_eq!(state.scratch_storage().0, before.0, "reconstruction must retain shard slot storage");
-        assert_eq!(state.scratch_storage().1, before.1, "unused error storage must not be rebuilt");
-    }
-
    #[tokio::test]
    async fn erasure_decode_reader_reports_short_source() {
        let erasure = Erasure::new(4, 2, 32);
@@ -18,12 +18,10 @@ use crate::disk::error_reduce::{
 };
 use crate::erasure::coding::BitrotWriterWrapper;
 use crate::erasure::coding::Erasure;
-use crate::erasure::coding::erasure::EncodedBlock;
 use crate::runtime::sources as runtime_sources;
 use bytes::{Bytes, BytesMut};
 use futures::StreamExt;
 use futures::stream::FuturesUnordered;
-use rustfs_utils::HashAlgorithm;
 use std::sync::Arc;
 use std::time::Instant;
 use std::vec;
@@ -166,7 +164,6 @@ where
    if total == 0 { Ok(None) } else { Ok(Some(total)) }
 }

-#[allow(dead_code, reason = "byte accounting asserted by this file's tests (backlog#1823)")]
 fn queued_block_bytes(block: &[Bytes]) -> usize {
    block.iter().map(Bytes::len).sum()
 }
@@ -226,8 +223,8 @@ async fn send_queued<T>(
    sender.send(InflightEntry::new(entry, bytes)).await
 }

-fn queued_batch_bytes(batch: &[EncodedBlock]) -> usize {
-    batch.iter().map(EncodedBlock::queued_bytes).sum()
+fn queued_batch_bytes(batch: &[Vec<Bytes>]) -> usize {
+    batch.iter().map(|block| queued_block_bytes(block)).sum()
 }

 fn dominant_error_summary_label(summary: &WriteQuorumFailureSummary) -> &'static str {
@@ -339,7 +336,7 @@ impl<'a> MultiWriter<'a> {
        }
    }

-    async fn write_shard(writer_opt: &mut Option<BitrotWriterWrapper>, err: &mut Option<Error>, shard: &[u8]) {
+    async fn write_shard(writer_opt: &mut Option<BitrotWriterWrapper>, err: &mut Option<Error>, shard: &Bytes) {
        match writer_opt {
            Some(writer) => {
                match writer.write(shard).await {
@@ -364,20 +361,12 @@ impl<'a> MultiWriter<'a> {
    }

    pub async fn write(&mut self, data: Vec<Bytes>) -> std::io::Result<()> {
-        self.write_shards(data.iter().map(Bytes::as_ref)).await
-    }
-
-    async fn write_block(&mut self, block: &EncodedBlock) -> std::io::Result<()> {
-        self.write_shards(block.shards()).await
-    }
-
-    async fn write_shards<'b>(&mut self, shards: impl ExactSizeIterator<Item = &'b [u8]>) -> std::io::Result<()> {
-        assert_eq!(shards.len(), self.writers.len());
+        assert_eq!(data.len(), self.writers.len());

        let budget = self.next_progress_budget();
        {
            let mut futures = FuturesUnordered::new();
-            for ((writer_opt, err), shard) in self.writers.iter_mut().zip(self.errs.iter_mut()).zip(shards) {
+            for ((writer_opt, err), shard) in self.writers.iter_mut().zip(self.errs.iter_mut()).zip(data.iter()) {
                if err.is_some() {
                    continue; // Skip if we already have an error for this writer
                }
@@ -501,10 +490,10 @@ impl<'a> MultiWriter<'a> {
 }

 impl Erasure {
-    async fn encode_block(self: Arc<Self>, encode_buf: Vec<u8>, len: usize) -> std::io::Result<(EncodedBlock, Vec<u8>)> {
+    async fn encode_block(self: Arc<Self>, encode_buf: Vec<u8>, len: usize) -> std::io::Result<(Vec<Bytes>, Vec<u8>)> {
        let encode_stage_start = stage_timer_if_enabled();
        let encode_once = move || {
-            let res = self.encode_data_block(&encode_buf[..len]);
+            let res = self.encode_data(&encode_buf[..len]);
            (res, encode_buf)
        };

@@ -529,9 +518,9 @@ impl Erasure {
        Ok((res?, returned_buf))
    }

-    async fn encode_block_bytes_mut(self: Arc<Self>, encode_buf: BytesMut, len: usize) -> std::io::Result<EncodedBlock> {
+    async fn encode_block_bytes_mut(self: Arc<Self>, encode_buf: BytesMut, len: usize) -> std::io::Result<Vec<Bytes>> {
        let encode_stage_start = stage_timer_if_enabled();
-        let encode_once = move || self.encode_data_bytes_mut_block(encode_buf, len);
+        let encode_once = move || self.encode_data_bytes_mut(encode_buf, len);

        let res = match tokio::runtime::Handle::current().runtime_flavor() {
            // Same rationale as encode_block: inline the short EC burst on the
@@ -587,46 +576,13 @@ impl Erasure {
            ));
        }

-        let block = self.encode_data_owned_block(buf)?;
+        let shards = self.encode_data_owned(buf)?;
        let mut mw = MultiWriter::new(writers, quorum);
-        mw.write_block(&block).await?;
+        mw.write(shards).await?;
        mw.shutdown().await?;
        Ok((reader, total))
    }

-    /// Encode a small inline object directly into its per-disk bitrot payloads.
-    /// The returned bytes are the same `[hash][shard]` representation produced
-    /// by `BitrotWriter`, ready to be embedded in each disk's staged `xl.meta`.
-    #[hotpath::measure(impl_type = "Erasure")]
-    pub(crate) async fn encode_inline_shards_with_size_hint<R>(
-        self: Arc<Self>,
-        mut reader: R,
-        size_hint: usize,
-    ) -> std::io::Result<(R, usize, Vec<Bytes>)>
-    where
-        R: AsyncRead + Send + Sync + Unpin,
-    {
-        use tokio::io::AsyncReadExt;
-
-        let mut buf = Vec::with_capacity(small_ingest_capacity(&self, size_hint));
-        let total = reader.read_to_end(&mut buf).await?;
-        if total == 0 {
-            return Ok((reader, 0, Vec::new()));
-        }
-
-        let block = self.encode_data_owned_block(buf)?;
-        let mut inline_shards = Vec::with_capacity(block.shards().len());
-        for shard in block.shards() {
-            let hash = HashAlgorithm::HighwayHash256S.hash_encode(shard);
-            let mut encoded = BytesMut::with_capacity(hash.as_ref().len() + shard.len());
-            encoded.extend_from_slice(hash.as_ref());
-            encoded.extend_from_slice(shard);
-            inline_shards.push(encoded.freeze());
-        }
-
-        Ok((reader, total, inline_shards))
-    }
-
    #[hotpath::measure(impl_type = "Erasure")]
    pub async fn encode<R>(
        self: Arc<Self>,
@@ -668,7 +624,7 @@ impl Erasure {
        let expanded_block_bytes = self.shard_size().saturating_mul(self.total_shard_count());
        let max_inflight_bytes = erasure_encode_max_inflight_bytes();
        let inflight_blocks = encode_channel_capacity(expanded_block_bytes, max_inflight_bytes);
-        let (tx, mut rx) = mpsc::channel::<InflightEntry<EncodedBlock>>(inflight_blocks);
+        let (tx, mut rx) = mpsc::channel::<InflightEntry<Vec<Bytes>>>(inflight_blocks);

        let mut task = AbortOnDropTask::new(tokio::spawn(async move {
            let block_size = self.block_size;
@@ -690,7 +646,7 @@ impl Erasure {
                            let encode_buf = buf;
                            let res = self.clone().encode_block_bytes_mut(encode_buf, n).await?;
                            buf = BytesMut::with_capacity(ingest_capacity);
-                            let queued_bytes = res.queued_bytes();
+                            let queued_bytes = queued_block_bytes(&res);
                            let _producer_stage = rustfs_io_metrics::track_ec_encode_producer_bytes(queued_bytes);
                            let send_wait_stage_start = stage_timer_if_enabled();
                            if let Err(err) = send_queued(&tx, res, queued_bytes).await {
@@ -720,7 +676,7 @@ impl Erasure {
                            let encode_buf = std::mem::take(&mut buf);
                            let (res, returned_buf) = self.clone().encode_block(encode_buf, n).await?;
                            buf = returned_buf;
-                            let queued_bytes = res.queued_bytes();
+                            let queued_bytes = queued_block_bytes(&res);
                            let _producer_stage = rustfs_io_metrics::track_ec_encode_producer_bytes(queued_bytes);
                            let send_wait_stage_start = stage_timer_if_enabled();
                            if let Err(err) = send_queued(&tx, res, queued_bytes).await {
@@ -764,9 +720,9 @@ impl Erasure {
            if block.is_empty() {
                break;
            }
-            let _writer_stage = rustfs_io_metrics::track_ec_encode_writer_bytes(block.queued_bytes());
+            let _writer_stage = rustfs_io_metrics::track_ec_encode_writer_bytes(queued_block_bytes(&block));
            let write_stage_start = stage_timer_if_enabled();
-            if let Err(err) = writers.write_block(&block).await {
+            if let Err(err) = writers.write(block).await {
                write_err = Some(err);
                break;
            }
@@ -813,7 +769,7 @@ impl Erasure {
        let inflight_blocks = encode_channel_capacity(expanded_block_bytes, max_inflight_bytes);
        let batch_blocks = encode_batch_block_count().min(inflight_blocks);
        let channel_capacity = inflight_blocks.div_ceil(batch_blocks).max(1);
-        let (tx, mut rx) = mpsc::channel::<InflightEntry<Vec<EncodedBlock>>>(channel_capacity);
+        let (tx, mut rx) = mpsc::channel::<InflightEntry<Vec<Vec<Bytes>>>>(channel_capacity);

        let mut task = AbortOnDropTask::new(tokio::spawn(async move {
            let block_size = self.block_size;
@@ -830,7 +786,7 @@ impl Erasure {
                        let encode_buf = std::mem::take(&mut buf);
                        let (res, returned_buf) = self.clone().encode_block(encode_buf, n).await?;
                        buf = returned_buf;
-                        let queued_bytes = res.queued_bytes();
+                        let queued_bytes = queued_block_bytes(&res);
                        pending_batch_bytes = pending_batch_bytes.saturating_add(queued_bytes);
                        pending_batch.push(res);
                        drop(pending_batch_stage.take());
@@ -889,7 +845,7 @@ impl Erasure {
            let _writer_stage = rustfs_io_metrics::track_ec_encode_writer_bytes(queued_batch_bytes(&batch));
            let write_stage_start = stage_timer_if_enabled();
            for block in batch {
-                if let Err(err) = writers.write_block(&block).await {
+                if let Err(err) = writers.write(block).await {
                    write_err = Some(err);
                    break;
                }
@@ -1939,11 +1895,7 @@ mod tests {
        let baseline = rustfs_io_metrics::current_ec_encode_inflight_bytes();
        let (tx, rx) = mpsc::channel(2);
        let mut rx = rx;
-        let erasure = Erasure::new(1, 0, 16);
-        let batch = vec![
-            erasure.encode_data_block(b"queued").expect("first block should encode"),
-            erasure.encode_data_block(b"batch").expect("second block should encode"),
-        ];
+        let batch = vec![vec![Bytes::from_static(b"queued")], vec![Bytes::from_static(b"batch")]];
        let batch_bytes = queued_batch_bytes(&batch);

        send_queued(&tx, batch, batch_bytes).await.expect("batch should be queued");
@@ -2165,39 +2117,6 @@ mod tests {
        );
    }

-    #[tokio::test]
-    async fn cancelling_inline_small_drops_stalled_write() {
-        const BLOCK_SIZE: usize = 16;
-
-        let (writer_entered_tx, writer_entered) = oneshot::channel();
-        let writes = Arc::new(std::sync::atomic::AtomicUsize::new(0));
-        let mut writers = vec![Some(bitrot_writer_plain(
-            StallOnWriteWithSignal {
-                entered: Some(writer_entered_tx),
-                writes: writes.clone(),
-            },
-            BLOCK_SIZE,
-        ))];
-        let erasure = Arc::new(Erasure::new(1, 0, BLOCK_SIZE));
-        let reader = tokio::io::BufReader::new(Cursor::new(vec![0xA5; BLOCK_SIZE - 1]));
-        let encode = tokio::spawn(async move { erasure.encode_inline_small(reader, &mut writers, 1).await });
-
-        tokio::time::timeout(Duration::from_secs(1), writer_entered)
-            .await
-            .expect("inline writer should enter before cancellation")
-            .expect("stalling writer should signal entry");
-        encode.abort();
-        assert!(
-            matches!(encode.await, Err(err) if err.is_cancelled()),
-            "inline encode task should be cancelled"
-        );
-        assert_eq!(
-            writes.load(std::sync::atomic::Ordering::SeqCst),
-            1,
-            "cancellation must drop the stalled write instead of polling it again"
-        );
-    }
-
    #[tokio::test]
    async fn encode_returns_unexpected_eof_for_truncated_limited_reader() {
        let committed = Arc::new(Mutex::new(Vec::new()));
@@ -2317,11 +2236,11 @@ mod tests {
            .expect("bytesmut encode should succeed on current-thread runtime");

        let expected_shard_size = payload.len().div_ceil(erasure.data_shards);
-        assert_eq!(shards.shards().len(), erasure.total_shard_count());
-        assert!(shards.shards().all(|shard| shard.len() == expected_shard_size));
+        assert_eq!(shards.len(), erasure.total_shard_count());
+        assert!(shards.iter().all(|shard| shard.len() == expected_shard_size));

        let mut restored = Vec::new();
-        for shard in shards.shards().take(erasure.data_shards) {
+        for shard in shards.iter().take(erasure.data_shards) {
            restored.extend_from_slice(shard);
        }
        restored.truncate(payload.len());
@@ -2424,41 +2343,6 @@ mod tests {
        assert!(committed.lock().unwrap().is_empty());
    }

-    #[tokio::test]
-    async fn encode_inline_shards_matches_writer_bitrot_layout() {
-        const DATA_SHARDS: usize = 2;
-        const PARITY_SHARDS: usize = 2;
-        const BLOCK_SIZE: usize = 64;
-        let checksum_algo = HashAlgorithm::HighwayHash256S;
-        for uses_legacy in [false, true] {
-            let erasure = Arc::new(Erasure::new_with_options(DATA_SHARDS, PARITY_SHARDS, BLOCK_SIZE, uses_legacy));
-            for payload in [Vec::new(), vec![0xA5], vec![0x5A; BLOCK_SIZE - 1], vec![0xC3; BLOCK_SIZE]] {
-                let reader = tokio::io::BufReader::new(Cursor::new(payload.clone()));
-                let (_reader, total, inline_shards) = erasure
-                    .clone()
-                    .encode_inline_shards_with_size_hint(reader, payload.len())
-                    .await
-                    .expect("inline shards should encode");
-
-                assert_eq!(total, payload.len());
-                if payload.is_empty() {
-                    assert!(inline_shards.is_empty());
-                    continue;
-                }
-
-                let raw_shards = erasure.encode_data(&payload).expect("reference shards should encode");
-                assert_eq!(inline_shards.len(), DATA_SHARDS + PARITY_SHARDS);
-                for (inline, raw) in inline_shards.iter().zip(raw_shards) {
-                    let mut writer =
-                        BitrotWriterWrapper::new(CustomWriter::new_inline_buffer(), raw.len(), checksum_algo.clone());
-                    writer.write(&raw).await.expect("reference writer should accept shard");
-                    writer.shutdown().await.expect("reference writer should shutdown");
-                    assert_eq!(inline.as_ref(), writer.into_inline_data().expect("reference writer should retain bytes"));
-                }
-            }
-        }
-    }
-
    /// encode_inline_small: small payload is encoded into the correct number of shards
    /// and each writer receives data after shutdown.
    #[tokio::test]
@@ -2622,7 +2506,7 @@ mod tests {
        assert_eq!(&next[..], &data[16..]);
    }

-    async fn committed_shards_for_pipeline(pipeline: EncodePipeline, uses_legacy: bool, payload: &[u8]) -> Vec<Vec<u8>> {
+    async fn committed_shards_for_ingest_mode(use_bytesmut_ingest: bool, uses_legacy: bool, payload: &[u8]) -> Vec<Vec<u8>> {
        const DATA_SHARDS: usize = 2;
        const PARITY_SHARDS: usize = 2;
        const TOTAL_SHARDS: usize = DATA_SHARDS + PARITY_SHARDS;
@@ -2636,16 +2520,10 @@ mod tests {

        let erasure = Arc::new(Erasure::new_with_options(DATA_SHARDS, PARITY_SHARDS, BLOCK_SIZE, uses_legacy));
        let reader = tokio::io::BufReader::new(Cursor::new(payload.to_vec()));
-        let (_reader, total) = match pipeline {
-            EncodePipeline::Vec => {
-                erasure
-                    .encode_with_ingest_mode(reader, &mut writers, DATA_SHARDS, false)
-                    .await
-            }
-            EncodePipeline::BytesMut => erasure.encode_with_ingest_mode(reader, &mut writers, DATA_SHARDS, true).await,
-            EncodePipeline::Batched => erasure.encode_batched(reader, &mut writers, DATA_SHARDS).await,
-        }
-        .expect("encode should succeed");
+        let (_reader, total) = erasure
+            .encode_with_ingest_mode(reader, &mut writers, DATA_SHARDS, use_bytesmut_ingest)
+            .await
+            .expect("encode should succeed");
        assert_eq!(total, payload.len());

        committed
@@ -2654,64 +2532,31 @@ mod tests {
            .collect()
    }

-    async fn expected_committed_shards(uses_legacy: bool, payload: &[u8]) -> Vec<Vec<u8>> {
-        const DATA_SHARDS: usize = 2;
-        const PARITY_SHARDS: usize = 2;
-        const TOTAL_SHARDS: usize = DATA_SHARDS + PARITY_SHARDS;
-        const BLOCK_SIZE: usize = 64;
-
-        let committed: Vec<Arc<Mutex<Vec<u8>>>> = (0..TOTAL_SHARDS).map(|_| Arc::new(Mutex::new(Vec::new()))).collect();
-        let mut writers: Vec<BitrotWriterWrapper> = committed
-            .iter()
-            .map(|c| bitrot_writer(DeferredCommitWriter::new(c.clone()), BLOCK_SIZE / DATA_SHARDS))
-            .collect();
-        let erasure = Erasure::new_with_options(DATA_SHARDS, PARITY_SHARDS, BLOCK_SIZE, uses_legacy);
-
-        for block in payload.chunks(BLOCK_SIZE) {
-            let shards = erasure.encode_data(block).expect("reference block should encode");
-            for (writer, shard) in writers.iter_mut().zip(shards) {
-                let written = writer.write(&shard).await.expect("reference shard should write");
-                assert_eq!(written, shard.len());
-            }
-        }
-        for writer in &mut writers {
-            writer.shutdown().await.expect("reference writer should commit");
-        }
-
-        committed
-            .iter()
-            .map(|c| c.lock().expect("committed buffer should be lockable").clone())
-            .collect()
-    }
-
-    /// The streaming and batched paths must produce the same bitrot-wrapped shard
-    /// bytes as the public block encoder for both shard-size formulas and all block
-    /// boundary shapes.
+    /// HP-10 (rustfs/backlog#931) merge gate: the BytesMut ingest path must produce
+    /// byte-for-byte identical shard streams to the default Vec ingest path, for both
+    /// legacy-aware shard-size formulas, across empty, sub-block, exactly-full-block,
+    /// and multi-block-with-partial-tail payloads.
    #[tokio::test]
    async fn bytesmut_ingest_matches_vec_ingest_byte_for_byte() {
        const BLOCK_SIZE: usize = 64;
        let payloads: Vec<Vec<u8>> = vec![
            Vec::new(),
-            vec![1],
-            vec![2; BLOCK_SIZE - 1],
+            b"tiny".to_vec(),
            (0..BLOCK_SIZE as u32).map(|i| i as u8).collect(), // exactly one full block
-            vec![4; BLOCK_SIZE + 1],
-            vec![3u8; BLOCK_SIZE * 4],                                           // whole number of blocks
+            vec![3u8; BLOCK_SIZE * 4],                         // whole number of blocks
            (0..(BLOCK_SIZE * 3 + 7) as u32).map(|i| (i % 251) as u8).collect(), // partial tail
        ];

        for uses_legacy in [false, true] {
            for payload in &payloads {
-                let expected = expected_committed_shards(uses_legacy, payload).await;
-                for pipeline in [EncodePipeline::Vec, EncodePipeline::BytesMut, EncodePipeline::Batched] {
-                    let actual = committed_shards_for_pipeline(pipeline, uses_legacy, payload).await;
-                    assert_eq!(
-                        actual,
-                        expected,
-                        "streaming shards must match the public block encoder (legacy={uses_legacy}, payload_len={})",
-                        payload.len()
-                    );
-                }
+                let vec_path = committed_shards_for_ingest_mode(false, uses_legacy, payload).await;
+                let bytesmut_path = committed_shards_for_ingest_mode(true, uses_legacy, payload).await;
+                assert_eq!(
+                    vec_path,
+                    bytesmut_path,
+                    "ingest paths must be byte-identical (legacy={uses_legacy}, payload_len={})",
+                    payload.len()
+                );
            }
        }
    }
@@ -29,58 +29,12 @@ use tokio::io::AsyncRead;
 use tracing::warn;
 use uuid::Uuid;

-pub(crate) struct EncodedBlock {
-    data: Bytes,
-    shard_size: usize,
-}
-
-impl EncodedBlock {
-    fn empty() -> Self {
-        Self {
-            data: Bytes::new(),
-            shard_size: 0,
-        }
-    }
-
-    pub(crate) fn is_empty(&self) -> bool {
-        self.data.is_empty()
-    }
-
-    pub(crate) fn queued_bytes(&self) -> usize {
-        self.data.len()
-    }
-
-    pub(crate) fn shards(&self) -> impl ExactSizeIterator<Item = &[u8]> {
-        debug_assert!(self.shard_size > 0, "only non-empty encoded blocks reach shard writers");
-        debug_assert_eq!(self.data.len() % self.shard_size, 0);
-        self.data.chunks_exact(self.shard_size)
-    }
-
-    fn into_shards(mut self, shard_count: usize) -> Vec<Bytes> {
-        if self.shard_size == 0 {
-            return vec![Bytes::new(); shard_count];
-        }
-
-        let mut shards = Vec::with_capacity(shard_count);
-        for _ in 0..shard_count {
-            shards.push(self.data.split_to(self.shard_size));
-        }
-        shards
-    }
-}
-
 const MODERN_MAX_TOTAL_SHARDS: usize = <reed_solomon_erasure::galois_8::Field as reed_solomon_erasure::Field>::ORDER;
 const MODERN_REED_SOLOMON_CACHE_MAX_ENTRIES: usize = 64;
-const LEGACY_REED_SOLOMON_CACHE_MAX_ENTRIES: usize = 16;
-// Vec growth may retain twice the requested logical length. Keeping the logical
-// workspace at half the budget bounds each cached workspace's shard allocation to 1 MiB.
-const LEGACY_REED_SOLOMON_CACHE_MAX_LOGICAL_SHARD_BYTES_PER_WORKSPACE: usize = 512 * 1024;

 type ModernReedSolomonCache = RwLock<HashMap<(usize, usize), Arc<ReedSolomon>>>;
-type LegacyReedSolomonCache = RwLock<HashMap<(usize, usize), Arc<LegacyReedSolomonEncoder>>>;

 static MODERN_REED_SOLOMON_CACHE: OnceLock<ModernReedSolomonCache> = OnceLock::new();
-static LEGACY_REED_SOLOMON_CACHE: OnceLock<LegacyReedSolomonCache> = OnceLock::new();

 /// Errors returned when constructing an [`Erasure`] codec.
 #[derive(Debug, thiserror::Error)]
@@ -147,61 +101,43 @@ pub fn calc_shard_size_legacy(block_size: usize, data_shards: usize) -> usize {
 struct LegacyReedSolomonEncoder {
    data_shards: usize,
    parity_shards: usize,
-    cache_workspaces: bool,
-    encoder_cache: RwLock<Option<reed_solomon_simd::ReedSolomonEncoder>>,
-    decoder_cache: RwLock<Option<reed_solomon_simd::ReedSolomonDecoder>>,
+    encoder_cache: std::sync::RwLock<Option<reed_solomon_simd::ReedSolomonEncoder>>,
+    decoder_cache: std::sync::RwLock<Option<reed_solomon_simd::ReedSolomonDecoder>>,
+}
+
+impl Clone for LegacyReedSolomonEncoder {
+    fn clone(&self) -> Self {
+        Self {
+            data_shards: self.data_shards,
+            parity_shards: self.parity_shards,
+            encoder_cache: std::sync::RwLock::new(None),
+            decoder_cache: std::sync::RwLock::new(None),
+        }
+    }
 }

 impl LegacyReedSolomonEncoder {
-    fn new(data_shards: usize, parity_shards: usize) -> io::Result<Self> {
-        Self::with_workspace_cache(data_shards, parity_shards, false)
-    }
-
-    fn with_workspace_cache(data_shards: usize, parity_shards: usize, cache_workspaces: bool) -> io::Result<Self> {
+    fn new(_data_shards: usize, _parity_shards: usize) -> io::Result<Self> {
        Ok(Self {
-            data_shards,
-            parity_shards,
-            cache_workspaces,
-            encoder_cache: RwLock::new(None),
-            decoder_cache: RwLock::new(None),
+            data_shards: _data_shards,
+            parity_shards: _parity_shards,
+            encoder_cache: std::sync::RwLock::new(None),
+            decoder_cache: std::sync::RwLock::new(None),
        })
    }

-    fn logical_shard_bytes_upper_bound(&self, shard_len: usize) -> Option<usize> {
-        let aligned_shard_len = shard_len.checked_add(63)?.checked_div(64)?.checked_mul(64)?;
-        let high_rate_decoder_work_count = self
-            .parity_shards
-            .checked_next_power_of_two()?
-            .checked_add(self.data_shards)?
-            .checked_next_power_of_two()?;
-        let low_rate_decoder_work_count = self
-            .data_shards
-            .checked_next_power_of_two()?
-            .checked_add(self.parity_shards)?
-            .checked_next_power_of_two()?;
-        aligned_shard_len.checked_mul(high_rate_decoder_work_count.max(low_rate_decoder_work_count))
-    }
-
-    fn should_cache_workspace(&self, shard_len: usize) -> bool {
-        self.cache_workspaces
-            && self
-                .logical_shard_bytes_upper_bound(shard_len)
-                .is_some_and(|bytes| bytes <= LEGACY_REED_SOLOMON_CACHE_MAX_LOGICAL_SHARD_BYTES_PER_WORKSPACE)
-    }
-
    fn encode(&self, shards: SmallVec<[&mut [u8]; 16]>) -> io::Result<()> {
        let mut shards_vec: Vec<&mut [u8]> = shards.into_vec();
        if shards_vec.is_empty() {
            return Ok(());
        }
        let shard_len = shards_vec[0].len();
-        let cached_encoder = self
-            .encoder_cache
-            .write()
-            .map_err(|_| io::Error::other("Failed to acquire encoder cache lock"))?
-            .take();
        let mut encoder = {
-            match cached_encoder {
+            let mut cache_guard = self
+                .encoder_cache
+                .write()
+                .map_err(|_| io::Error::other("Failed to acquire encoder cache lock"))?;
+            match cache_guard.take() {
                Some(mut cached) => {
                    if cached.reset(self.data_shards, self.parity_shards, shard_len).is_err() {
                        reed_solomon_simd::ReedSolomonEncoder::new(self.data_shards, self.parity_shards, shard_len)
@@ -228,15 +164,10 @@ impl LegacyReedSolomonEncoder {
            }
        }
        drop(result);
-        if self.should_cache_workspace(shard_len) {
-            let mut cache = self
-                .encoder_cache
-                .write()
-                .map_err(|_| io::Error::other("Failed to return encoder to cache"))?;
-            if cache.is_none() {
-                *cache = Some(encoder);
-            }
-        }
+        *self
+            .encoder_cache
+            .write()
+            .map_err(|_| io::Error::other("Failed to return encoder to cache"))? = Some(encoder);
        Ok(())
    }

@@ -250,13 +181,13 @@ impl LegacyReedSolomonEncoder {
            .find_map(|s| s.as_ref().map(|v| v.len()))
            .ok_or_else(|| io::Error::other("No valid shards found for reconstruction"))?;

-        let cached_decoder = self
-            .decoder_cache
-            .write()
-            .map_err(|_| io::Error::other("Failed to acquire decoder cache lock"))?
-            .take();
        let mut decoder = {
-            match cached_decoder {
+            let mut cache_guard = self
+                .decoder_cache
+                .write()
+                .map_err(|_| io::Error::other("Failed to acquire decoder cache lock"))?;
+
+            match cache_guard.take() {
                Some(mut cached_decoder) => {
                    if let Err(e) = cached_decoder.reset(self.data_shards, self.parity_shards, shard_len) {
                        warn!("Failed to reset SIMD decoder: {:?}, creating new one", e);
@@ -303,15 +234,10 @@ impl LegacyReedSolomonEncoder {

        drop(result);

-        if self.should_cache_workspace(shard_len) {
-            let mut cache = self
-                .decoder_cache
-                .write()
-                .map_err(|_| io::Error::other("Failed to return decoder to cache"))?;
-            if cache.is_none() {
-                *cache = Some(decoder);
-            }
-        }
+        *self
+            .decoder_cache
+            .write()
+            .map_err(|_| io::Error::other("Failed to return decoder to cache"))? = Some(decoder);

        Ok(())
    }
@@ -469,39 +395,6 @@ fn cached_modern_reed_solomon(data_shards: usize, parity_shards: usize) -> Resul
    Ok(encoder)
 }

-fn cached_legacy_reed_solomon(data_shards: usize, parity_shards: usize) -> io::Result<Arc<LegacyReedSolomonEncoder>> {
-    let cache = LEGACY_REED_SOLOMON_CACHE.get_or_init(|| RwLock::new(HashMap::new()));
-    cached_legacy_reed_solomon_in(cache, data_shards, parity_shards)
-}
-
-fn cached_legacy_reed_solomon_in(
-    cache: &LegacyReedSolomonCache,
-    data_shards: usize,
-    parity_shards: usize,
-) -> io::Result<Arc<LegacyReedSolomonEncoder>> {
-    let key = (data_shards, parity_shards);
-    if let Some(encoder) = cache
-        .read()
-        .unwrap_or_else(|poisoned| poisoned.into_inner())
-        .get(&key)
-        .cloned()
-    {
-        return Ok(encoder);
-    }
-
-    let mut cache = cache.write().unwrap_or_else(|poisoned| poisoned.into_inner());
-    if let Some(existing) = cache.get(&key) {
-        return Ok(Arc::clone(existing));
-    }
-    if cache.len() < LEGACY_REED_SOLOMON_CACHE_MAX_ENTRIES {
-        let encoder = Arc::new(LegacyReedSolomonEncoder::with_workspace_cache(data_shards, parity_shards, true)?);
-        cache.insert(key, Arc::clone(&encoder));
-        return Ok(encoder);
-    }
-    drop(cache);
-    Ok(Arc::new(LegacyReedSolomonEncoder::new(data_shards, parity_shards)?))
-}
-
 fn encode_parity_shards<F>(shards: &mut [Option<Vec<u8>>], data_shards: usize, parity_shards: usize, encode: F) -> io::Result<()>
 where
    F: FnOnce(SmallVec<[&mut [u8]; 16]>) -> io::Result<()>,
@@ -618,7 +511,7 @@ pub struct Erasure {
    pub data_shards: usize,
    pub parity_shards: usize,
    encoder: Option<ReedSolomonEncoder>,
-    legacy_encoder: Option<Arc<LegacyReedSolomonEncoder>>,
+    legacy_encoder: Option<LegacyReedSolomonEncoder>,
    pub block_size: usize,
    uses_legacy: bool,
    _id: Uuid,
@@ -754,7 +647,7 @@ impl Erasure {

        let legacy_encoder = if uses_legacy && parity_shards > 0 {
            Some(
-                cached_legacy_reed_solomon(data_shards, parity_shards)
+                LegacyReedSolomonEncoder::new(data_shards, parity_shards)
                    .map_err(|source| ErasureConstructionError::LegacyEncoder { source })?,
            )
        } else {
@@ -782,48 +675,106 @@ impl Erasure {
    #[tracing::instrument(level = "debug", skip_all, fields(data_len=data.len()))]
    #[hotpath::measure(impl_type = "Erasure")]
    pub fn encode_data(&self, data: &[u8]) -> io::Result<Vec<Bytes>> {
-        self.encode_data_block_inner(data)
-            .map(|block| block.into_shards(self.total_shard_count()))
-    }
+        let shard_size_fn = if self.uses_legacy {
+            calc_shard_size_legacy
+        } else {
+            calc_shard_size
+        };
+        let per_shard_size = shard_size_fn(data.len(), self.data_shards);
+        if per_shard_size == 0 {
+            return Ok(vec![Bytes::new(); self.total_shard_count()]);
+        }
+        let need_total_size = per_shard_size * self.total_shard_count();

-    #[tracing::instrument(level = "debug", skip_all, fields(data_len=data.len()))]
-    #[hotpath::measure(label = "Erasure::encode_data", impl_type = "Erasure")]
-    pub(crate) fn encode_data_block(&self, data: &[u8]) -> io::Result<EncodedBlock> {
-        self.encode_data_block_inner(data)
-    }
-
-    fn encode_data_block_inner(&self, data: &[u8]) -> io::Result<EncodedBlock> {
-        let mut data_buffer = BytesMut::with_capacity(self.encoded_capacity_for_data_len(data.len()));
+        let mut data_buffer = BytesMut::with_capacity(need_total_size);
        data_buffer.extend_from_slice(data);
-        self.encode_buffer(data_buffer, data.len())
+        data_buffer.resize(need_total_size, 0u8);
+
+        {
+            let data_slices: SmallVec<[&mut [u8]; 16]> = data_buffer.chunks_exact_mut(per_shard_size).collect();
+
+            if self.parity_shards > 0 {
+                if self.uses_legacy {
+                    if let Some(encoder) = self.legacy_encoder.as_ref() {
+                        encoder.encode(data_slices)?;
+                    } else {
+                        warn!("parity_shards > 0, uses_legacy but legacy_encoder is None");
+                    }
+                } else if let Some(encoder) = self.encoder.as_ref() {
+                    encoder.encode(data_slices)?;
+                } else {
+                    warn!("parity_shards > 0, but encoder is None");
+                }
+            }
+        }
+
+        // Zero-copy split, all shards reference data_buffer
+        let mut data_buffer = data_buffer.freeze();
+        let mut shards = Vec::with_capacity(self.total_shard_count());
+        for _ in 0..self.total_shard_count() {
+            let shard = data_buffer.split_to(per_shard_size);
+            shards.push(shard);
+        }
+
+        Ok(shards)
    }

    /// Encode owned data, avoiding a copy when the caller already has a heap buffer.
    /// Falls back to copying into a new buffer if zero-copy conversion fails.
    #[hotpath::measure(impl_type = "Erasure")]
    pub fn encode_data_owned(&self, data: Vec<u8>) -> io::Result<Vec<Bytes>> {
-        self.encode_data_owned_block_inner(data)
-            .map(|block| block.into_shards(self.total_shard_count()))
-    }
+        let shard_size_fn = if self.uses_legacy {
+            calc_shard_size_legacy
+        } else {
+            calc_shard_size
+        };
+        let per_shard_size = shard_size_fn(data.len(), self.data_shards);
+        if per_shard_size == 0 {
+            return Ok(vec![Bytes::new(); self.total_shard_count()]);
+        }
+        let need_total_size = per_shard_size * self.total_shard_count();

-    #[hotpath::measure(label = "Erasure::encode_data_owned", impl_type = "Erasure")]
-    pub(crate) fn encode_data_owned_block(&self, data: Vec<u8>) -> io::Result<EncodedBlock> {
-        self.encode_data_owned_block_inner(data)
-    }
-
-    fn encode_data_owned_block_inner(&self, data: Vec<u8>) -> io::Result<EncodedBlock> {
-        let data_len = data.len();
        // Try zero-copy: Vec<u8> -> Bytes -> BytesMut (succeeds when refcount == 1)
-        let data_buffer = match Bytes::from(data).try_into_mut() {
-            Ok(data_buffer) => data_buffer,
+        let mut data_buffer = match Bytes::from(data).try_into_mut() {
+            Ok(mut bm) => {
+                bm.resize(need_total_size, 0u8);
+                bm
+            }
            Err(b) => {
                // Rare path: refcount != 1, fall back to copy
-                let mut data_buffer = BytesMut::with_capacity(self.encoded_capacity_for_data_len(data_len));
-                data_buffer.extend_from_slice(&b);
-                data_buffer
+                let mut bm = BytesMut::with_capacity(need_total_size);
+                bm.extend_from_slice(&b);
+                bm.resize(need_total_size, 0u8);
+                bm
            }
        };
-        self.encode_buffer(data_buffer, data_len)
+
+        {
+            let data_slices: SmallVec<[&mut [u8]; 16]> = data_buffer.chunks_exact_mut(per_shard_size).collect();
+
+            if self.parity_shards > 0 {
+                if self.uses_legacy {
+                    if let Some(encoder) = self.legacy_encoder.as_ref() {
+                        encoder.encode(data_slices)?;
+                    } else {
+                        warn!("parity_shards > 0, uses_legacy but legacy_encoder is None");
+                    }
+                } else if let Some(encoder) = self.encoder.as_ref() {
+                    encoder.encode(data_slices)?;
+                } else {
+                    warn!("parity_shards > 0, but encoder is None");
+                }
+            }
+        }
+
+        let mut data_buffer = data_buffer.freeze();
+        let mut shards = Vec::with_capacity(self.total_shard_count());
+        for _ in 0..self.total_shard_count() {
+            let shard = data_buffer.split_to(per_shard_size);
+            shards.push(shard);
+        }
+
+        Ok(shards)
    }

    /// Encode data from an owned `BytesMut` buffer, avoiding the initial copy
@@ -835,17 +786,7 @@ impl Erasure {
    /// `data_len <= block_size` — both shard-size formulas are monotone in
    /// `data_len` — so this function never reallocates the buffer.
    #[hotpath::measure(impl_type = "Erasure")]
-    pub fn encode_data_bytes_mut(&self, data_buffer: BytesMut, data_len: usize) -> io::Result<Vec<Bytes>> {
-        self.encode_buffer(data_buffer, data_len)
-            .map(|block| block.into_shards(self.total_shard_count()))
-    }
-
-    #[hotpath::measure(label = "Erasure::encode_data_bytes_mut", impl_type = "Erasure")]
-    pub(crate) fn encode_data_bytes_mut_block(&self, data_buffer: BytesMut, data_len: usize) -> io::Result<EncodedBlock> {
-        self.encode_buffer(data_buffer, data_len)
-    }
-
-    fn encode_buffer(&self, mut data_buffer: BytesMut, data_len: usize) -> io::Result<EncodedBlock> {
+    pub fn encode_data_bytes_mut(&self, mut data_buffer: BytesMut, data_len: usize) -> io::Result<Vec<Bytes>> {
        let shard_size_fn = if self.uses_legacy {
            calc_shard_size_legacy
        } else {
@@ -853,7 +794,7 @@ impl Erasure {
        };
        let per_shard_size = shard_size_fn(data_len, self.data_shards);
        if per_shard_size == 0 {
-            return Ok(EncodedBlock::empty());
+            return Ok(vec![Bytes::new(); self.total_shard_count()]);
        }
        let need_total_size = per_shard_size * self.total_shard_count();

@@ -880,10 +821,14 @@ impl Erasure {
            }
        }

-        Ok(EncodedBlock {
-            data: data_buffer.freeze(),
-            shard_size: per_shard_size,
-        })
+        let mut data_buffer = data_buffer.freeze();
+        let mut shards = Vec::with_capacity(self.total_shard_count());
+        for _ in 0..self.total_shard_count() {
+            let shard = data_buffer.split_to(per_shard_size);
+            shards.push(shard);
+        }
+
+        Ok(shards)
    }

    /// Decode and reconstruct missing data shards in-place.
@@ -1110,10 +1055,6 @@ impl Erasure {
    ///
    /// # Errors
    /// Returns error if reading from reader fails or if callback returns error
-    #[allow(
-        dead_code,
-        reason = "callback encode path exercised only by this file's tests (backlog#1823)"
-    )]
    pub(crate) async fn encode_stream_callback_async<F, Fut, E, R>(
        self: std::sync::Arc<Self>,
        reader: &mut R,
@@ -1476,7 +1417,7 @@ mod tests {
        assert_eq!(cloned.block_size, legacy.block_size);
        assert!(cloned.uses_legacy);

-        let data = b"legacy clone should preserve SIMD codec behavior";
+        let data = b"legacy clone should keep independent SIMD caches";
        let encoded = cloned.encode_data(data).expect("legacy clone should encode");
        let mut shards = optional_shards(&encoded);
        shards[0] = None;
@@ -1484,93 +1425,6 @@ mod tests {
        assert_eq!(recover_data(&shards, cloned.data_shards, data.len()), data);
    }

-    #[test]
-    fn legacy_codecs_share_process_cache_across_erasure_instances() {
-        let first = Erasure::new_with_options(6, 3, 64, true)
-            .legacy_encoder
-            .expect("legacy codec should be initialized");
-        let second = Erasure::new_with_options(6, 3, 128, true)
-            .legacy_encoder
-            .expect("same legacy shard layout should be initialized");
-
-        assert!(Arc::ptr_eq(&first, &second));
-    }
-
-    #[test]
-    fn legacy_workspace_cache_rejects_oversize_buffers_and_isolates_layouts() {
-        let four_plus_two = Erasure::new_with_options(4, 2, 64, true)
-            .legacy_encoder
-            .expect("legacy codec should be initialized");
-        let four_plus_one = Erasure::new_with_options(4, 1, 64, true)
-            .legacy_encoder
-            .expect("distinct parity layout should be initialized");
-        let three_plus_two = Erasure::new_with_options(3, 2, 64, true)
-            .legacy_encoder
-            .expect("distinct data layout should be initialized");
-
-        assert!(!Arc::ptr_eq(&four_plus_two, &four_plus_one));
-        assert!(!Arc::ptr_eq(&four_plus_two, &three_plus_two));
-        assert_eq!(four_plus_two.logical_shard_bytes_upper_bound(64 * 1024), Some(512 * 1024));
-        assert!(four_plus_two.should_cache_workspace(64 * 1024));
-        assert!(!four_plus_two.should_cache_workspace(64 * 1024 + 1));
-
-        let nine_plus_seven =
-            LegacyReedSolomonEncoder::with_workspace_cache(9, 7, true).expect("9+7 legacy codec should construct");
-        assert_eq!(nine_plus_seven.logical_shard_bytes_upper_bound(16 * 1024), Some(512 * 1024));
-        assert!(nine_plus_seven.should_cache_workspace(16 * 1024));
-        assert!(!nine_plus_seven.should_cache_workspace(16 * 1024 + 1));
-
-        let uncached = LegacyReedSolomonEncoder::new(4, 2).expect("uncached legacy codec should construct");
-        assert!(!uncached.should_cache_workspace(64));
-    }
-
-    #[test]
-    fn saturated_legacy_codec_cache_does_not_retain_more_workspaces() {
-        let cache = RwLock::new(HashMap::new());
-        for parity_shards in 1..=LEGACY_REED_SOLOMON_CACHE_MAX_ENTRIES {
-            let cached =
-                cached_legacy_reed_solomon_in(&cache, 32, parity_shards).expect("cacheable legacy codec should construct");
-            assert!(cached.cache_workspaces);
-        }
-
-        let uncached =
-            cached_legacy_reed_solomon_in(&cache, 31, 1).expect("uncached legacy codec should construct after saturation");
-        assert!(!uncached.cache_workspaces);
-        assert_eq!(
-            cache.read().expect("cache lock should remain healthy").len(),
-            LEGACY_REED_SOLOMON_CACHE_MAX_ENTRIES
-        );
-    }
-
-    #[test]
-    fn concurrent_legacy_codecs_preserve_byte_exact_results() {
-        let barrier = Arc::new(std::sync::Barrier::new(2));
-        let payloads = [vec![0x35; 257], vec![0xca; 1025]];
-
-        std::thread::scope(|scope| {
-            let handles = payloads.each_ref().map(|payload| {
-                let barrier = Arc::clone(&barrier);
-                scope.spawn(move || {
-                    let erasure = Erasure::new_with_options(6, 3, 2048, true);
-                    barrier.wait();
-                    let encoded = erasure.encode_data(payload).expect("concurrent legacy encode should succeed");
-                    barrier.wait();
-
-                    let mut shards = optional_shards(&encoded);
-                    shards[0] = None;
-                    erasure
-                        .decode_data(&mut shards)
-                        .expect("concurrent legacy decode should reconstruct the missing shard");
-                    recover_data(&shards, erasure.data_shards, payload.len())
-                })
-            });
-
-            for (handle, payload) in handles.into_iter().zip(payloads.iter()) {
-                assert_eq!(handle.join().expect("concurrent legacy codec worker should not panic"), *payload);
-            }
-        });
-    }
-
    #[test]
    fn legacy_verify_reports_invalid_empty_valid_and_corrupt_parity_sets() {
        let legacy = LegacyReedSolomonEncoder::new(2, 2).expect("legacy encoder should construct");
@@ -1644,16 +1498,10 @@ mod tests {
    fn encode_data_owned_matches_borrowed_path() {
        for uses_legacy in [false, true] {
            let erasure = Erasure::new_with_options(4, 2, 64, uses_legacy);
-            for data in [
-                Vec::new(),
-                vec![0xA5; 1],
-                b"small payload".to_vec(),
-                (0_u8..37).collect(),
-                vec![0xA5; erasure.block_size - 1],
-                vec![0x5A; erasure.block_size],
-            ] {
-                assert_owned_encode_matches_borrowed(&erasure, data);
-            }
+
+            assert_owned_encode_matches_borrowed(&erasure, Vec::new());
+            assert_owned_encode_matches_borrowed(&erasure, b"small payload".to_vec());
+            assert_owned_encode_matches_borrowed(&erasure, (0_u8..37).collect());
        }
    }

@@ -1699,52 +1547,6 @@ mod tests {
        }
    }

-    #[test]
-    fn streaming_encoded_block_uses_one_contiguous_backing_buffer() {
-        for uses_legacy in [false, true] {
-            let erasure = Erasure::new_with_options(8, 8, 64, uses_legacy);
-
-            for data_len in [0, 1, 63, 64] {
-                let data = (0..data_len).map(|i| i as u8).collect::<Vec<_>>();
-                let expected = erasure.encode_data(&data).expect("public encode should succeed");
-                let borrowed = erasure
-                    .encode_data_block(&data)
-                    .expect("borrowed streaming encode should succeed");
-                let owned = erasure
-                    .encode_data_owned_block(data.clone())
-                    .expect("owned streaming encode should succeed");
-                let bytes_mut = erasure
-                    .encode_data_bytes_mut_block(BytesMut::from(&data[..]), data.len())
-                    .expect("BytesMut streaming encode should succeed");
-
-                assert_eq!(borrowed.queued_bytes(), owned.queued_bytes());
-                assert_eq!(borrowed.queued_bytes(), bytes_mut.queued_bytes());
-
-                if data_len == 0 {
-                    assert!(expected.iter().all(Bytes::is_empty));
-                    assert!(borrowed.is_empty());
-                    assert!(owned.is_empty());
-                    assert!(bytes_mut.is_empty());
-                    continue;
-                }
-
-                assert!(borrowed.shards().eq(expected.iter().map(Bytes::as_ref)));
-                assert!(owned.shards().eq(expected.iter().map(Bytes::as_ref)));
-                assert!(bytes_mut.shards().eq(expected.iter().map(Bytes::as_ref)));
-                assert_eq!(borrowed.shards().len(), 16);
-                let first = borrowed.shards().next().expect("encoded block should have shards").as_ptr();
-                for (index, shard) in borrowed.shards().enumerate() {
-                    assert_eq!(shard.as_ptr(), first.wrapping_add(index * shard.len()));
-                }
-            }
-        }
-        assert_eq!(
-            std::mem::size_of::<EncodedBlock>(),
-            std::mem::size_of::<Bytes>() + std::mem::size_of::<usize>(),
-            "queue entries must contain one backing buffer handle, not per-shard handles"
-        );
-    }
-
    /// HP-10 capacity invariant: both shard-size formulas are monotone in `data_len`,
    /// so pre-reserving `shard_size(block_size) * total_shard_count` covers the
    /// `need_total_size` of every block-or-smaller payload and the ingest buffer
@@ -13,6 +13,7 @@
 // limitations under the License.

 // #730: erasure codec migration keeps staged streaming decode paths in this module.
+#![allow(dead_code)]

 pub(crate) mod codec;
 pub(crate) mod coding;
@@ -13,12 +13,13 @@
 // limitations under the License.

 // #730: error taxonomy still exposes compatibility variants while callers move to contracts.
+#![allow(dead_code)]

 use crate::bucket::error::BucketMetadataError;
 use crate::disk::error::DiskError;
 use crate::storage_api_contracts::{error::StorageErrorCode, range::HTTPRangeError};
 use rustfs_utils::path::decode_dir_object;
-use s3s::S3ErrorCode;
+use s3s::{S3Error, S3ErrorCode};

 pub type Error = StorageError;
 pub type Result<T> = core::result::Result<T, Error>;
@@ -901,7 +902,6 @@ pub fn is_err_decommission_running(err: &Error) -> bool {
    matches!(err, &StorageError::DecommissionAlreadyRunning)
 }

-#[allow(dead_code, reason = "predicate asserted by this file's tests (backlog#1823)")]
 pub fn is_err_rebalance_running(err: &Error) -> bool {
    matches!(err, &StorageError::RebalanceAlreadyRunning)
 }
@@ -910,11 +910,14 @@ pub fn is_err_operation_canceled(err: &Error) -> bool {
    matches!(err, &StorageError::OperationCanceled)
 }

-#[allow(dead_code, reason = "predicate asserted by this file's tests (backlog#1823)")]
 pub fn is_err_not_initialized(err: &Error) -> bool {
    err.to_string().contains("errServerNotInitialized") || err.to_string().contains("ServerNotInitialized")
 }

+pub fn is_err_io(err: &Error) -> bool {
+    matches!(err, &StorageError::Io(_))
+}
+
 /// Strict "not found" predicate that only matches genuine object/version/volume
 /// absence errors: `FileNotFound`/`VolumeNotFound`/`FileVersionNotFound`/
 /// `ObjectNotFound`/`VersionNotFound`.
@@ -1075,6 +1078,21 @@ pub struct GenericError {

 #[derive(Debug, thiserror::Error, PartialEq, Eq)]
 pub enum ObjectApiError {
+    #[error("Operation timed out")]
+    OperationTimedOut,
+
+    #[error("etag of the object has changed")]
+    InvalidETag,
+
+    #[error("BackendDown")]
+    BackendDown(String),
+
+    #[error("Unsupported headers in Metadata")]
+    UnsupportedMetadata,
+
+    #[error("Method not allowed: {}/{}", .0.bucket, .0.object)]
+    MethodNotAllowed(GenericError),
+
    #[error("The operation is not valid for the current state of the object {}/{}({})", .0.bucket, .0.object, .0.version_id)]
    InvalidObjectState(GenericError),
 }
@@ -1091,6 +1109,96 @@ pub struct ErrorResponse {
    pub host_id: String,
 }

+pub fn error_resp_to_object_err(err: ErrorResponse, params: Vec<&str>) -> std::io::Error {
+    let mut bucket = "";
+    let mut object = "";
+    let mut version_id = "";
+    if !params.is_empty() {
+        bucket = params[0];
+    }
+    if params.len() >= 2 {
+        object = params[1];
+    }
+    if params.len() >= 3 {
+        version_id = params[2];
+    }
+
+    if is_network_or_host_down(&err.to_string(), false) {
+        return std::io::Error::other(ObjectApiError::BackendDown(format!("{err}")));
+    }
+
+    let err_ = std::io::Error::other(err.to_string());
+    let r_err = err;
+    let err;
+    let bucket = bucket.to_string();
+    let object = object.to_string();
+    let version_id = version_id.to_string();
+
+    match r_err.code {
+        S3ErrorCode::BucketNotEmpty => {
+            err = std::io::Error::other(StorageError::BucketNotEmpty("".to_string()).to_string());
+        }
+        S3ErrorCode::InvalidBucketName => {
+            err = std::io::Error::other(StorageError::BucketNameInvalid(bucket));
+        }
+        S3ErrorCode::InvalidPart => {
+            err = std::io::Error::other(StorageError::InvalidPart(0, bucket, object /* , version_id */));
+        }
+        S3ErrorCode::NoSuchBucket => {
+            err = std::io::Error::other(StorageError::BucketNotFound(bucket));
+        }
+        S3ErrorCode::NoSuchKey => {
+            if !object.is_empty() {
+                err = std::io::Error::other(StorageError::ObjectNotFound(bucket, object));
+            } else {
+                err = std::io::Error::other(StorageError::BucketNotFound(bucket));
+            }
+        }
+        S3ErrorCode::NoSuchVersion => {
+            if !object.is_empty() {
+                err = std::io::Error::other(StorageError::ObjectNotFound(bucket, object)); //, version_id);
+            } else {
+                err = std::io::Error::other(StorageError::BucketNotFound(bucket));
+            }
+        }
+        S3ErrorCode::AccessDenied => {
+            err = std::io::Error::other(StorageError::PrefixAccessDenied(bucket, object));
+        }
+        S3ErrorCode::NoSuchUpload => {
+            err = std::io::Error::other(StorageError::InvalidUploadID(bucket, object, version_id));
+        }
+        _ => {
+            err = err_;
+        }
+    }
+
+    err
+}
+
+pub fn storage_to_object_err(err: Error, params: Vec<&str>) -> S3Error {
+    let storage_err = &err;
+    let mut bucket: String = "".to_string();
+    let mut object: String = "".to_string();
+    if !params.is_empty() {
+        bucket = params[0].to_string();
+    }
+    if params.len() >= 2 {
+        object = decode_dir_object(params[1]);
+    }
+    match storage_err {
+        StorageError::MethodNotAllowed => S3Error::with_message(
+            S3ErrorCode::MethodNotAllowed,
+            ObjectApiError::MethodNotAllowed(GenericError {
+                bucket,
+                object,
+                ..Default::default()
+            })
+            .to_string(),
+        ),
+        _ => s3s::S3Error::with_message(S3ErrorCode::Custom("err".into()), err.to_string()),
+    }
+}
+
 #[cfg(test)]
 mod tests {
    use super::*;
@@ -13,6 +13,8 @@
 // limitations under the License.

 // #730: event target types are retained for notification owner migration.
+#![allow(dead_code)]

 pub mod name;
+pub mod targetid;
 pub mod targetlist;
@@ -0,0 +1,25 @@
+#![allow(clippy::all)]
+// Copyright 2024 RustFS Team
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+pub struct TargetID {
+    id: String,
+    name: String,
+}
+
+impl TargetID {
+    fn to_string(&self) -> String {
+        format!("{}:{}", self.id, self.name)
+    }
+}
@@ -12,20 +12,18 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.

+use crate::event::targetid::TargetID;
 use std::sync::atomic::AtomicI64;

-/// Placeholder notification target list held by `EventNotifier`.
-///
-/// The working notification stack lives in `rustfs-notify` / `rustfs-targets`;
-/// this type never grew past its counter. `total_events` is read by the
-/// notifier's log line but nothing increments it, so that field reports zero.
 #[derive(Default)]
-#[allow(
-    dead_code,
-    reason = "held only by the dead ecstore EventNotifier; see services/event_notification.rs (backlog#1823)"
-)]
 pub struct TargetList {
+    pub current_send_calls: AtomicI64,
    pub total_events: AtomicI64,
+    pub events_skipped: AtomicI64,
+    pub events_errors_total: AtomicI64,
+    //pub targets: HashMap<TargetID, Target>,
+    //pub queue:   AsyncEvent,
+    //pub targetStats: HashMap<TargetID, TargetStat>,
 }

 impl TargetList {
@@ -33,3 +31,14 @@ impl TargetList {
        TargetList::default()
    }
 }
+
+struct TargetStat {
+    current_send_calls: i64,
+    total_events: i64,
+    failed_events: i64,
+}
+
+struct TargetIDResult {
+    id: TargetID,
+    err: std::io::Error,
+}
@@ -22,13 +22,12 @@ use crate::diagnostics::get::{
 #[cfg(feature = "hotpath")]
 use crate::disk::FileWriter;
 use crate::disk::{self, DiskAPI as _, DiskStore, FileReader, MmapCopyStageMetrics, error::DiskError};
-use crate::erasure::coding::{BitrotReader, BitrotWriterWrapper, CustomWriter, ShardChunkRead};
+use crate::erasure::coding::{BitrotReader, BitrotWriterWrapper, CustomWriter};
 use bytes::Bytes;
 use rustfs_config::{
    DEFAULT_OBJECT_MMAP_READ_ENABLE, DEFAULT_OBJECT_MMAP_READ_MAX_LENGTH, ENV_OBJECT_MMAP_READ_ENABLE,
    ENV_OBJECT_MMAP_READ_MAX_LENGTH, ENV_OBJECT_ZERO_COPY_ENABLE,
 };
-use rustfs_rio::ChunkReaderBox;
 use rustfs_utils::HashAlgorithm;
 use std::future::Future;
 use std::io::{self, Cursor};
@@ -52,25 +51,13 @@ tokio::task_local! {
 /// (rustfs/backlog#1159). Everything else is a stream and keeps the old path.
 pub enum ShardReader {
    InMemory(Cursor<Bytes>),
-    Chunked(ChunkReaderBox),
    Stream(Box<dyn AsyncRead + Send + Sync + Unpin>),
 }

-#[cfg(test)]
-impl ShardReader {
-    pub(crate) fn inline_bytes(&self) -> Option<&Bytes> {
-        match self {
-            Self::InMemory(cursor) => Some(cursor.get_ref()),
-            Self::Chunked(_) | Self::Stream(_) => None,
-        }
-    }
-}
-
 impl AsyncRead for ShardReader {
    fn poll_read(self: Pin<&mut Self>, cx: &mut Context<'_>, buf: &mut tokio::io::ReadBuf<'_>) -> Poll<std::io::Result<()>> {
        match self.get_mut() {
            Self::InMemory(cursor) => Pin::new(cursor).poll_read(cx, buf),
-            Self::Chunked(reader) => Pin::new(&mut **reader).poll_read(cx, buf),
            Self::Stream(reader) => Pin::new(reader).poll_read(cx, buf),
        }
    }
@@ -80,19 +67,7 @@ impl crate::erasure::coding::ShardSource for ShardReader {
    fn try_take_block(&mut self, n: usize) -> Option<Bytes> {
        match self {
            Self::InMemory(cursor) => cursor.try_take_block(n),
-            Self::Chunked(_) | Self::Stream(_) => None,
-        }
-    }
-
-    fn poll_read_chunk(self: Pin<&mut Self>, cx: &mut Context<'_>, max: usize) -> Poll<io::Result<ShardChunkRead>> {
-        let Self::Chunked(reader) = self.get_mut() else {
-            return Poll::Ready(Ok(ShardChunkRead::Unsupported));
-        };
-        match Pin::new(&mut **reader).poll_read_chunk(cx, max) {
-            Poll::Ready(Ok(Some(chunk))) => Poll::Ready(Ok(ShardChunkRead::Chunk(chunk))),
-            Poll::Ready(Ok(None)) => Poll::Ready(Ok(ShardChunkRead::Eof)),
-            Poll::Ready(Err(err)) => Poll::Ready(Err(err)),
-            Poll::Pending => Poll::Pending,
+            Self::Stream(_) => None,
        }
    }
 }
@@ -370,17 +345,6 @@ async fn open_disk_reader(
    let metrics_path = metrics_path.filter(|_| rustfs_io_metrics::get_stage_metrics_enabled());
    let stage_metrics_enabled = metrics_path.is_some();

-    // Preserve HTTP body ownership only on healthy remote reads. Instrumented
-    // and local paths retain their existing AsyncRead wrappers.
-    if use_mmap_read
-        && !disk.is_local()
-        && !stage_metrics_enabled
-        && !cfg!(feature = "hotpath")
-        && let Some(reader) = disk.read_file_stream_chunks(bucket, path, offset, length).await?
-    {
-        return Ok(ShardReader::Chunked(reader));
-    }
-
    // Mmap-copy materializes the whole `offset..offset+length` range as one
    // owned allocation before any byte is served, and GET/heal shard reads
    // request the entire part span in one call. Over-cap reads (e.g. a huge
@@ -656,7 +620,7 @@ pub async fn create_bitrot_reader_from_bytes(
 }

 #[allow(clippy::too_many_arguments)]
-pub(crate) async fn create_bitrot_reader_from_bytes_with_stage_metrics(
+async fn create_bitrot_reader_from_bytes_with_stage_metrics(
    inline_data: Option<Bytes>,
    disk: Option<&DiskStore>,
    bucket: &str,
@@ -816,50 +780,6 @@ pub async fn create_bitrot_writer(
 #[cfg(test)]
 mod tests {
    use super::*;
-    use rustfs_rio::ChunkReader;
-    use std::collections::VecDeque;
-
-    struct TestChunkReader {
-        chunks: VecDeque<Bytes>,
-    }
-
-    impl TestChunkReader {
-        fn new(bytes: Bytes, fragment_sizes: &[usize]) -> Self {
-            let mut chunks = VecDeque::new();
-            let mut offset = 0;
-            for &size in fragment_sizes {
-                let end = (offset + size).min(bytes.len());
-                if offset < end {
-                    chunks.push_back(bytes.slice(offset..end));
-                }
-                offset = end;
-            }
-            if offset < bytes.len() {
-                chunks.push_back(bytes.slice(offset..));
-            }
-            Self { chunks }
-        }
-    }
-
-    impl AsyncRead for TestChunkReader {
-        fn poll_read(self: Pin<&mut Self>, _cx: &mut Context<'_>, _buf: &mut ReadBuf<'_>) -> Poll<io::Result<()>> {
-            Poll::Ready(Err(io::Error::other("test chunk reader must use chunk handoff")))
-        }
-    }
-
-    impl ChunkReader for TestChunkReader {
-        fn poll_read_chunk(mut self: Pin<&mut Self>, _cx: &mut Context<'_>, max: usize) -> Poll<io::Result<Option<Bytes>>> {
-            let Some(mut chunk) = self.chunks.pop_front() else {
-                return Poll::Ready(Ok(None));
-            };
-            let take = chunk.len().min(max);
-            if take < chunk.len() {
-                self.chunks.push_front(chunk.split_off(take));
-            }
-            chunk.truncate(take);
-            Poll::Ready(Ok(Some(chunk)))
-        }
-    }

    #[cfg(feature = "hotpath")]
    use crate::cluster::rpc::RemoteDisk;
@@ -1749,49 +1669,4 @@ mod tests {
        println!("error: {error:?}");
        assert_eq!(error, DiskError::DiskNotFound);
    }
-
-    #[tokio::test]
-    async fn shard_reader_chunked_path_verifies_fragmented_remote_block() {
-        const SHARD_SIZE: usize = 1024;
-        let algo = HashAlgorithm::HighwayHash256S;
-        let data = vec![42u8; SHARD_SIZE];
-        let mut encoded = Vec::new();
-        crate::erasure::coding::BitrotWriter::new(&mut encoded, SHARD_SIZE, algo.clone())
-            .write(&data)
-            .await
-            .expect("test shard should encode");
-
-        let source = TestChunkReader::new(Bytes::from(encoded), &[3, 7, 17, 31]);
-        let mut reader = BitrotReader::new(ShardReader::Chunked(Box::new(source)), SHARD_SIZE, algo, false);
-        let mut output = Vec::with_capacity(SHARD_SIZE);
-        reader
-            .read_appending(&mut output, SHARD_SIZE)
-            .await
-            .expect("fragmented remote shard should verify");
-
-        assert_eq!(output, data);
-    }
-
-    #[tokio::test]
-    async fn shard_reader_chunked_path_handles_more_than_one_poll_budget() {
-        const SHARD_SIZE: usize = 1024;
-        let algo = HashAlgorithm::HighwayHash256S;
-        let data = vec![42u8; SHARD_SIZE];
-        let mut encoded = Vec::new();
-        crate::erasure::coding::BitrotWriter::new(&mut encoded, SHARD_SIZE, algo.clone())
-            .write(&data)
-            .await
-            .expect("test shard should encode");
-
-        let fragment_sizes = vec![1; encoded.len()];
-        let source = TestChunkReader::new(Bytes::from(encoded), &fragment_sizes);
-        let mut reader = BitrotReader::new(ShardReader::Chunked(Box::new(source)), SHARD_SIZE, algo, false);
-        let mut output = Vec::with_capacity(SHARD_SIZE);
-        reader
-            .read_appending(&mut output, SHARD_SIZE)
-            .await
-            .expect("fragmented remote shard should verify after multiple polls");
-
-        assert_eq!(output, data);
-    }
 }
@@ -31,13 +31,6 @@ pub const ENV_DISK_COMPRESSION_MIME_TYPES: &str = "RUSTFS_COMPRESSION_MIME_TYPES
 // Environment variable for additional extensions to exclude from compression (comma-separated, e.g. ".foo,.bar")
 pub const ENV_ADDED_EXCLUDE_COMPRESS_EXTENSIONS: &str = "RUSTFS_ADDED_EXCLUDE_COMPRESS_EXTENSIONS";

-// Environment variable to additionally enable disk compression for multipart uploads.
-// Default off: nodes from before the resumable decompressor fix fail transient reads of
-// compressed objects, so multipart compression stays dark until the operator confirms the
-// fleet has converged on a fixed build.
-// RUSTFS_COMPAT_TODO(multipart-compression-default-off-window): staged rollout switch for restored multipart compression, flipping the default to enabled on retirement. Remove after the minimum supported direct-upgrade release ships the resumable DecompressReader.
-pub const ENV_DISK_COMPRESSION_MULTIPART_ENABLED: &str = "RUSTFS_COMPRESSION_MULTIPART_ENABLED";
-
 pub const DEFAULT_DISK_COMPRESS_EXTENSIONS: &str = ".txt,.log,.csv,.json,.tar,.xml,.bin";
 pub const DEFAULT_DISK_COMPRESS_MIME_TYPES: &str = "text/*,application/json,application/xml,binary/octet-stream";

@@ -178,21 +171,6 @@ pub fn is_disk_compression_enabled() -> bool {
    DISK_COMPRESSION_CONFIG.get_or_init(parse_disk_compression_config).enabled
 }

-// Parsed once at first use, mirroring DISK_COMPRESSION_CONFIG.
-static MULTIPART_DISK_COMPRESSION_ENABLED: OnceLock<bool> = OnceLock::new();
-
-/// Whether multipart uploads may advertise disk compression. Requires the
-/// regular disk-compression gates to pass as well; this is the staged-rollout
-/// switch that keeps multipart compression dark during rolling upgrades from
-/// builds whose decompressor was not yet resumable.
-pub fn is_multipart_disk_compression_enabled() -> bool {
-    *MULTIPART_DISK_COMPRESSION_ENABLED.get_or_init(|| {
-        env::var(ENV_DISK_COMPRESSION_MULTIPART_ENABLED)
-            .map(|s| matches!(s.to_ascii_lowercase().as_str(), "true" | "on" | "1"))
-            .unwrap_or(false)
-    })
-}
-
 fn is_disk_compressible_with_config(headers: &http::HeaderMap, object_name: &str, config: &DiskCompressionConfig) -> bool {
    // Check if disk compression is enabled (read once at first use, then fixed for process lifetime)
    if !config.enabled {
@@ -13,6 +13,7 @@
 // limitations under the License.

 // #730: I/O backend selection keeps test-only and staged rio helpers scoped here.
+#![allow(dead_code)]

 pub(crate) mod bitrot;
 pub(crate) mod compress;
@@ -25,20 +25,9 @@ use tokio::io::AsyncRead;

 #[cfg(feature = "rio-v2")]
 const MINIO_S2_COMPRESSION_SCHEME: &str = "klauspost/compress/s2";
-// The S2 padding multiple rio-v2 pads compressed streams to before
-// encryption. Only the padding test asserts it today, so the lib target sees
-// it as unused (backlog#1823).
 #[cfg(feature = "rio-v2")]
-#[allow(dead_code, reason = "on-disk contract asserted by the rio-v2 padding test (backlog#1823)")]
 const ENCRYPTED_S2_PADDING_MULTIPLE: usize = 256;

-/// Which rio implementation this build compiled in. Only the feature-seam
-/// guard test in lib.rs reads it, so the lib target sees it as unused
-/// (backlog#1823).
-#[allow(
-    dead_code,
-    reason = "asserted by the rio backend feature-seam test in lib.rs (backlog#1823)"
-)]
 pub const fn backend_name() -> &'static str {
    #[cfg(feature = "rio-v2")]
    {
@@ -64,6 +53,17 @@ pub fn compression_metadata_value(algorithm: CompressionAlgorithm) -> String {
    }
 }

+pub fn compression_scheme_to_algorithm(scheme: &str) -> std::io::Result<CompressionAlgorithm> {
+    #[cfg(feature = "rio-v2")]
+    if scheme.eq_ignore_ascii_case(MINIO_S2_COMPRESSION_SCHEME) {
+        // rio_v2 currently routes all compressed-object handling through the S2
+        // reader implementation, so the enum is only a placeholder token here.
+        return Ok(CompressionAlgorithm::default());
+    }
+
+    CompressionAlgorithm::from_str(scheme)
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum ReadCompressionBackend {
    Legacy,
@@ -82,11 +82,6 @@ pub fn compression_scheme_to_read_plan(scheme: &str) -> std::io::Result<(Compres
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum ReadEncryptionBackend {
    Legacy,
-    // Never constructed today — every read still selects Legacy — but the
-    // decrypt paths below carry live match arms for it. This is the rio-v2
-    // read seam (backlog#1638 / #1835), not dead code: deleting the variant
-    // would delete those arms with it.
-    #[allow(dead_code, reason = "rio-v2 read seam; match arms below are live (backlog#1823)")]
    V2,
 }

@@ -21,8 +21,7 @@ use tracing::debug;

 /// Supported set sizes this is used to find the optimal
 /// single set size.
-pub(crate) const MAX_ERASURE_SET_DRIVE_COUNT: usize = 16;
-const SET_SIZES: [usize; 15] = [2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, MAX_ERASURE_SET_DRIVE_COUNT];
+const SET_SIZES: [usize; 15] = [2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16];
 const ENV_RUSTFS_ERASURE_SET_DRIVE_COUNT: &str = "RUSTFS_ERASURE_SET_DRIVE_COUNT";

 #[derive(Deserialize, Debug, Default)]
@@ -328,7 +327,7 @@ fn possible_set_counts(set_size: usize) -> Vec<usize> {

 /// checks whether given count is a valid set size for erasure coding.
 fn is_valid_set_size(count: usize) -> bool {
-    count >= SET_SIZES[0] && count <= MAX_ERASURE_SET_DRIVE_COUNT
+    count >= SET_SIZES[0] && count <= SET_SIZES[SET_SIZES.len() - 1]
 }

 /// Final set size with all the symmetry accounted for.
@@ -209,12 +209,15 @@ impl AsMut<Vec<Endpoints>> for PoolEndpointList {
 }

 impl PoolEndpointList {
-    /// Creates a list of endpoints per pool, resolves their relevant hostnames
-    /// and discovers whether those are local or remote.
-    ///
-    /// The policy and host overrides let tests inject an explicit startup
-    /// topology convergence policy and local endpoint host instead of
-    /// resolving them from the environment; production passes `None` for both.
+    /// creates a list of endpoints per pool, resolves their relevant
+    /// hostnames and discovers those are local or remote.
+    async fn create_pool_endpoints(server_addr: &str, disks_layout: &DisksLayout) -> Result<Self> {
+        Self::create_pool_endpoints_with(server_addr, disks_layout, None, None).await
+    }
+
+    /// Same as [`create_pool_endpoints`] but lets tests inject an explicit
+    /// startup topology convergence policy and local endpoint host instead of
+    /// resolving them from the environment.
    async fn create_pool_endpoints_with(
        server_addr: &str,
        disks_layout: &DisksLayout,
@@ -591,10 +594,6 @@ impl PoolEndpointList {
 }

 const DNS_RETRY_BASE_DELAY: Duration = Duration::from_millis(500);
-#[allow(
-    dead_code,
-    reason = "retry-cap bound asserted by this file's dns_retry_delay tests (backlog#1823)"
-)]
 const DNS_RETRY_MAX_DELAY: Duration = Duration::from_secs(8);
 const DNS_RETRY_JITTER_PERCENT: u64 = 20;
 /// Minimum spacing between "still retrying" warnings so a long orchestrated
@@ -13,6 +13,7 @@
 // limitations under the License.

 // #730: set-layout contracts are staged while ECStore ownership boundaries shrink.
+#![allow(dead_code)]

 //! Static ECStore layout boundaries.
 //!
@@ -4,7 +4,6 @@ use std::io::{Error, Result};
 use uuid::Uuid;

 #[derive(Debug, Clone, PartialEq, Eq)]
-#[allow(dead_code, reason = "ESET-001 layout model; exercised by this file's tests (backlog#1823)")]
 pub(crate) struct StaticSetLayoutSnapshot {
    pub(crate) deployment_id: Uuid,
    pub(crate) set_count: usize,
@@ -13,7 +12,6 @@ pub(crate) struct StaticSetLayoutSnapshot {
    pub(crate) distribution_algo: DistributionAlgoVersion,
 }

-#[allow(dead_code, reason = "ESET-001 layout model; exercised by this file's tests (backlog#1823)")]
 impl StaticSetLayoutSnapshot {
    pub(crate) fn from_format(format: &FormatV3) -> Self {
        let disk_ids = format.erasure.sets.clone();
@@ -41,20 +39,17 @@ impl StaticSetLayoutSnapshot {
 }

 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
-#[allow(dead_code, reason = "ESET-001 layout model; exercised by this file's tests (backlog#1823)")]
 pub(crate) struct SetDiskPosition {
    pub(crate) set_index: usize,
    pub(crate) disk_index: usize,
 }

 #[derive(Debug, Clone, PartialEq, Eq)]
-#[allow(dead_code, reason = "ESET-001 layout model; exercised by this file's tests (backlog#1823)")]
 pub(crate) struct RuntimeSetLayoutPlan {
    pub(crate) sets: Vec<Vec<RuntimeSetDrivePlan>>,
    lock_hosts_by_set: Vec<Vec<String>>,
 }

-#[allow(dead_code, reason = "ESET-001 layout model; exercised by this file's tests (backlog#1823)")]
 impl RuntimeSetLayoutPlan {
    pub(crate) fn from_endpoint_hosts<S>(set_count: usize, drives_per_set: usize, endpoint_hosts: &[S]) -> Result<Self>
    where
@@ -113,7 +108,6 @@ impl RuntimeSetLayoutPlan {
 }

 #[derive(Debug, Clone, PartialEq, Eq)]
-#[allow(dead_code, reason = "ESET-001 layout model; exercised by this file's tests (backlog#1823)")]
 pub(crate) struct RuntimeSetDrivePlan {
    pub(crate) set_index: usize,
    pub(crate) disk_index: usize,
@@ -13,6 +13,7 @@
 // limitations under the License.

 // #730: object API readers keep staged compatibility paths during facade migration.
+#![allow(dead_code)]

 use crate::bucket::metadata_sys::get_versioning_config;
 use crate::bucket::replication::{
@@ -22,7 +23,7 @@ use crate::bucket::replication::{
 use crate::bucket::versioning::VersioningApi as _;
 use crate::config::storageclass;
 use crate::error::{Error, Result};
-use crate::io_support::rio::{HardLimitReader, HashReader};
+use crate::io_support::rio::{HashReader, LimitReader};
 use crate::storage_api_contracts::{
    lifecycle::{ExpirationOptions, TransitionedObject},
    range::HTTPRangeSpec,
@@ -15,7 +15,6 @@
 use super::*;

 use crate::io_support::rio::Index;
-use std::mem::MaybeUninit;

 #[cfg(feature = "rio-v2")]
 const DARE_PAYLOAD_SIZE: i64 = 64 * 1024;
@@ -449,16 +448,10 @@ impl GetObjectReader {
 }

 enum ReadTransform {
-    // Written but never read by production code: the enclosing struct already
-    // carries the same pair as `storage_offset`/`storage_length`. They survive
-    // as the read plan's test-visible record — four tests assert them by
-    // literal pattern (`Plain { visible_offset: 6, visible_length: 4 }`), which
-    // rustc does not count as a read.
-    #[allow(
-        dead_code,
-        reason = "asserted by literal pattern in this file's read-plan tests (backlog#1823)"
-    )]
-    Plain { visible_offset: usize, visible_length: i64 },
+    Plain {
+        visible_offset: usize,
+        visible_length: i64,
+    },
    Compressed {
        algorithm: CompressionAlgorithm,
        backend: crate::io_support::rio::ReadCompressionBackend,
@@ -479,15 +472,7 @@ enum ReadTransform {
    },
 }

-/// How an object's stored bytes must be fetched and transformed to serve a
-/// request.
-///
-/// Public so callers that fetch the stored bytes from somewhere other than the
-/// local erasure set — the remote-tier read path — can position their own fetch
-/// with [`ReadPlan::storage_offset`] / [`ReadPlan::storage_length`] and then
-/// hand the resulting stream to [`ReadPlan::into_object_reader`], instead of
-/// reimplementing the transform decisions (rustfs/rustfs#6025).
-pub struct ReadPlan {
+struct ReadPlan {
    storage_offset: usize,
    storage_length: i64,
    object_size: i64,
@@ -495,43 +480,6 @@ pub struct ReadPlan {
 }

 impl ReadPlan {
-    /// Byte offset into the object's **stored** bytes where the fetch must
-    /// start. Encrypted and compressed objects address their storage in a
-    /// different coordinate system than the plaintext range the caller asked
-    /// for, which is exactly the distinction this plan resolves.
-    pub fn storage_offset(&self) -> usize {
-        self.storage_offset
-    }
-
-    /// Number of **stored** bytes the fetch must deliver, in the same
-    /// coordinate system as [`Self::storage_offset`].
-    pub fn storage_length(&self) -> i64 {
-        self.storage_length
-    }
-
-    /// Build the plan for a request without consuming a stream, so a caller
-    /// that has to issue its own positioned fetch can read the offsets first.
-    pub async fn build_for_request(
-        rs: Option<HTTPRangeSpec>,
-        oi: &ObjectInfo,
-        opts: &ObjectOptions,
-        h: &HeaderMap<HeaderValue>,
-        resolver: Option<&dyn ObjectEncryptionResolver>,
-    ) -> Result<Self> {
-        Self::build_with_resolver(rs, oi, opts, h, resolver).await
-    }
-
-    /// Wrap `reader` — the stored bytes this plan asked for, already positioned
-    /// at [`Self::storage_offset`] — in the transforms that turn them into the
-    /// bytes the caller requested.
-    pub fn into_object_reader(
-        self,
-        reader: Box<dyn AsyncRead + Unpin + Send + Sync>,
-        oi: &ObjectInfo,
-    ) -> Result<GetObjectReader> {
-        self.into_reader(reader, oi).map(|(reader, _, _)| reader)
-    }
-
    #[cfg(test)]
    async fn build(rs: Option<HTTPRangeSpec>, oi: &ObjectInfo, opts: &ObjectOptions, h: &HeaderMap<HeaderValue>) -> Result<Self> {
        Self::build_with_resolver(rs, oi, opts, h, Some(&tests::TEST_RESOLVER)).await
@@ -545,17 +493,8 @@ impl ReadPlan {
        resolver: Option<&dyn ObjectEncryptionResolver>,
    ) -> Result<Self> {
        let mut rs = rs;
-        // A part number addresses the object's PLAINTEXT bytes. A restore read
-        // serves the stored representation instead (see
-        // [`restore_request_active`]), where that synthesized range would be
-        // reinterpreted as a storage range and truncate an encrypted or
-        // compressed payload by exactly its encoding overhead — the copy-back
-        // then fails its length check partway through
-        // (rustfs/rustfs#6025). An explicit caller range is already in storage
-        // coordinates on that path and is still honored.
        if let Some(part_number) = opts.part_number
            && rs.is_none()
-            && !restore_request_active(opts)
        {
            rs = http_range_spec_from_object_info(oi, part_number);
        }
@@ -808,7 +747,7 @@ impl ReadPlan {
                        }
                    }
                } else {
-                    Box::new(HardLimitReader::new(dec_reader, decompressed_length))
+                    Box::new(LimitReader::new(dec_reader, total_plaintext_size))
                };

                let mut object_info = oi.clone();
@@ -900,7 +839,7 @@ impl ReadPlan {
                            )?;
                            Box::new(ranged_reader)
                        } else {
-                            Box::new(HardLimitReader::new(decompressed_reader, total_plaintext_size_i64))
+                            Box::new(LimitReader::new(decompressed_reader, total_plaintext_size))
                        }
                    } else if plaintext_offset > 0 || plaintext_length != total_plaintext_size_i64 {
                        Box::new(RangedDecompressReader::new(
@@ -910,7 +849,7 @@ impl ReadPlan {
                            total_plaintext_size,
                        )?)
                    } else {
-                        Box::new(HardLimitReader::new(decrypted_reader, total_plaintext_size_i64))
+                        Box::new(LimitReader::new(decrypted_reader, total_plaintext_size))
                    };

                let mut object_info = oi.clone();
@@ -983,7 +922,7 @@ struct SkipReader<R> {
    inner: R,
    bytes_to_skip: usize,
    bytes_skipped: usize,
-    scratch: Box<[MaybeUninit<u8>]>,
+    scratch: Vec<u8>,
 }

 impl<R: AsyncRead + Unpin + Send + Sync> SkipReader<R> {
@@ -992,7 +931,7 @@ impl<R: AsyncRead + Unpin + Send + Sync> SkipReader<R> {
            inner,
            bytes_to_skip,
            bytes_skipped: 0,
-            scratch: Box::<[u8]>::new_uninit_slice(8192),
+            scratch: vec![0u8; 8192],
        }
    }
 }
@@ -1004,7 +943,7 @@ impl<R: AsyncRead + Unpin + Send + Sync> AsyncRead for SkipReader<R> {
        while this.bytes_skipped < this.bytes_to_skip {
            let remaining = this.bytes_to_skip - this.bytes_skipped;
            let scratch_len = remaining.min(this.scratch.len());
-            let mut scratch_buf = ReadBuf::uninit(&mut this.scratch[..scratch_len]);
+            let mut scratch_buf = ReadBuf::new(&mut this.scratch[..scratch_len]);
            match Pin::new(&mut this.inner).poll_read(cx, &mut scratch_buf) {
                Poll::Pending => return Poll::Pending,
                Poll::Ready(Err(err)) => return Poll::Ready(Err(err)),
@@ -1035,7 +974,7 @@ pub struct RangedDecompressReader<R: AsyncRead + Unpin + Send + Sync + 'static>
    target_length: usize,
    current_offset: usize,
    bytes_returned: usize,
-    scratch: Box<[MaybeUninit<u8>]>,
+    scratch: Vec<u8>,
    drain_on_done: bool,
    drain_task: Option<tokio::task::JoinHandle<()>>,
 }
@@ -1073,7 +1012,7 @@ impl<R: AsyncRead + Unpin + Send + Sync + 'static> RangedDecompressReader<R> {
            target_length: actual_length,
            current_offset: 0,
            bytes_returned: 0,
-            scratch: Box::<[u8]>::new_uninit_slice(8192),
+            scratch: vec![0u8; 8192],
            drain_on_done,
            drain_task: None,
        })
@@ -1123,7 +1062,7 @@ impl<R: AsyncRead + Unpin + Send + Sync + 'static> AsyncRead for RangedDecompres
            }

            let scratch_len = std::cmp::min(this.scratch.len(), std::cmp::max(buf_capacity, 1));
-            let mut temp_read_buf = ReadBuf::uninit(&mut this.scratch[..scratch_len]);
+            let mut temp_read_buf = ReadBuf::new(&mut this.scratch[..scratch_len]);

            let Some(inner) = this.inner.as_mut() else {
                return Poll::Ready(Ok(()));
@@ -1175,8 +1114,7 @@ impl<R: AsyncRead + Unpin + Send + Sync + 'static> AsyncRead for RangedDecompres
                            );

                            if bytes_to_return > 0 {
-                                let data_slice =
-                                    &temp_read_buf.filled()[data_start_in_buffer..data_start_in_buffer + bytes_to_return];
+                                let data_slice = &this.scratch[data_start_in_buffer..data_start_in_buffer + bytes_to_return];
                                buf.put_slice(data_slice);
                                this.bytes_returned += bytes_to_return;

@@ -1195,7 +1133,7 @@ impl<R: AsyncRead + Unpin + Send + Sync + 'static> AsyncRead for RangedDecompres
                            std::cmp::min(n, std::cmp::min(buf.remaining(), this.target_length - this.bytes_returned));

                        if bytes_to_return > 0 {
-                            buf.put_slice(&temp_read_buf.filled()[..bytes_to_return]);
+                            buf.put_slice(&this.scratch[..bytes_to_return]);
                            this.bytes_returned += bytes_to_return;

                            tracing::trace!("Returned {} bytes at offset {}", bytes_to_return, old_offset);
@@ -1265,7 +1203,20 @@ impl<R: AsyncRead + Unpin + Send + 'static> AsyncRead for StreamConsumer<R> {

 impl<R: AsyncRead + Unpin + Send + 'static> Drop for StreamConsumer<R> {
    fn drop(&mut self) {
-        self.ensure_consumer_started();
+        if self.consumer_task.is_none() && self.inner.is_some() {
+            let mut inner = self.inner.take().unwrap();
+            let task = tokio::spawn(async move {
+                let mut buf = [0u8; 8192];
+                loop {
+                    match inner.read(&mut buf).await {
+                        Ok(0) => break,    // EOF
+                        Ok(_) => continue, // Keep consuming
+                        Err(_) => break,   // Error, stop consuming
+                    }
+                }
+            });
+            self.consumer_task = Some(task);
+        }
    }
 }

@@ -1312,43 +1263,6 @@ mod tests {
    use temp_env::async_with_vars;
    use tokio::io::AsyncReadExt;

-    #[derive(Debug)]
-    struct PendingPartialReader {
-        data: &'static [u8],
-        position: usize,
-        pending: bool,
-    }
-
-    impl PendingPartialReader {
-        fn new(data: &'static [u8]) -> Self {
-            Self {
-                data,
-                position: 0,
-                pending: true,
-            }
-        }
-    }
-
-    impl AsyncRead for PendingPartialReader {
-        fn poll_read(mut self: Pin<&mut Self>, cx: &mut Context<'_>, buf: &mut ReadBuf<'_>) -> Poll<std::io::Result<()>> {
-            if self.pending {
-                self.pending = false;
-                cx.waker().wake_by_ref();
-                return Poll::Pending;
-            }
-            if self.position == self.data.len() {
-                return Poll::Ready(Ok(()));
-            }
-
-            let length = buf.remaining().min(3).min(self.data.len() - self.position);
-            let end = self.position + length;
-            buf.put_slice(&self.data[self.position..end]);
-            self.position = end;
-            self.pending = true;
-            Poll::Ready(Ok(()))
-        }
-    }
-
    const TEST_DIRECT_KEY_HEADER: &str = "x-rustfs-test-direct-key";
    const TEST_OBJECT_KEY_HEADER: &str = "x-rustfs-test-object-key";
    const TEST_NONCE_HEADER: &str = "x-rustfs-test-nonce";
@@ -1486,36 +1400,6 @@ mod tests {
        assert_eq!(result, b"World");
    }

-    #[tokio::test]
-    async fn uninitialized_scratch_preserves_partial_pending_and_eof_reads() {
-        let mut skipped = SkipReader::new(PendingPartialReader::new(b"0123456789abcdef"), 5);
-        let mut skipped_output = Vec::new();
-        skipped
-            .read_to_end(&mut skipped_output)
-            .await
-            .expect("skip reader should survive partial pending reads through EOF");
-        assert_eq!(skipped_output, b"56789abcdef");
-
-        let mut ranged = RangedDecompressReader::new(PendingPartialReader::new(b"0123456789abcdef"), 5, 7, 16)
-            .expect("valid range should construct");
-        let mut ranged_output = Vec::new();
-        ranged
-            .read_to_end(&mut ranged_output)
-            .await
-            .expect("range reader should survive partial pending reads through EOF");
-        assert_eq!(ranged_output, b"56789ab");
-    }
-
-    #[tokio::test]
-    async fn uninitialized_skip_scratch_reports_early_eof() {
-        let mut reader = SkipReader::new(PendingPartialReader::new(b"short"), 6);
-        let error = reader
-            .read_to_end(&mut Vec::new())
-            .await
-            .expect_err("EOF before the skip boundary must remain visible");
-        assert_eq!(error.kind(), std::io::ErrorKind::UnexpectedEof);
-    }
-
    #[tokio::test]
    async fn test_ranged_decompress_reader_from_start() {
        let original_data = b"Hello, World! This is a test.";
@@ -1781,423 +1665,6 @@ mod tests {
        assert_eq!(actual, b"fghijkl");
    }

-    /// Compresses one multipart part exactly like the write path does
-    /// (`WritePlan::with_compression` wraps each part in its own
-    /// `compression_reader`), returning the on-disk bytes and the storage-format
-    /// compression index.
-    async fn compressed_part_fixture(data: &[u8]) -> (Vec<u8>, Option<Bytes>) {
-        use crate::io_support::rio::TryGetIndex as _;
-        let mut compressor =
-            crate::io_support::rio::compression_reader(Cursor::new(data.to_vec()), CompressionAlgorithm::default(), false);
-        let mut compressed = Vec::new();
-        compressor.read_to_end(&mut compressed).await.expect("compress part stream");
-        let index = compressor
-            .try_get_index()
-            .map(crate::io_support::rio::compression_index_storage_bytes);
-        (compressed, index)
-    }
-
-    struct CompressedMultipartFixture {
-        object_info: ObjectInfo,
-        stored: Vec<u8>,
-        plaintext: Vec<u8>,
-    }
-
-    /// Builds the on-disk representation of a compressed multipart object: each
-    /// part is an independent compressed stream and the storage layer serves
-    /// their concatenation.
-    async fn compressed_multipart_fixture(part_sizes: &[usize]) -> CompressedMultipartFixture {
-        let pattern = b"compressed multipart read path fixture data ";
-        let mut plaintext = Vec::new();
-        let mut stored = Vec::new();
-        let mut parts = Vec::with_capacity(part_sizes.len());
-
-        for (i, part_size) in part_sizes.iter().enumerate() {
-            let mut part_plaintext = Vec::with_capacity(*part_size);
-            while part_plaintext.len() < *part_size {
-                part_plaintext.extend_from_slice(pattern);
-                part_plaintext.push(i as u8);
-            }
-            part_plaintext.truncate(*part_size);
-
-            let (compressed, index) = compressed_part_fixture(&part_plaintext).await;
-            parts.push(ObjectPartInfo {
-                number: i + 1,
-                size: compressed.len(),
-                actual_size: *part_size as i64,
-                index,
-                ..Default::default()
-            });
-            stored.extend_from_slice(&compressed);
-            plaintext.extend_from_slice(&part_plaintext);
-        }
-
-        let mut user_defined = HashMap::new();
-        rustfs_utils::http::insert_str(
-            &mut user_defined,
-            rustfs_utils::http::SUFFIX_COMPRESSION,
-            crate::io_support::rio::compression_metadata_value(CompressionAlgorithm::default()),
-        );
-        rustfs_utils::http::insert_str(&mut user_defined, rustfs_utils::http::SUFFIX_ACTUAL_SIZE, plaintext.len().to_string());
-
-        let object_info = ObjectInfo {
-            bucket: "test-bucket".to_string(),
-            name: "compressed-multipart".to_string(),
-            size: stored.len() as i64,
-            etag: Some(format!("6bcf86bed8807b8e78f0fc6e0a53079d-{}", part_sizes.len())),
-            parts: Arc::new(parts),
-            user_defined: Arc::new(user_defined),
-            ..Default::default()
-        };
-
-        CompressedMultipartFixture {
-            object_info,
-            stored,
-            plaintext,
-        }
-    }
-
-    /// Plans the read once to learn the storage window, then serves exactly that
-    /// window — mirroring how `set_disk` feeds the erasure read into the
-    /// returned reader.
-    async fn read_compressed_multipart(
-        fixture: &CompressedMultipartFixture,
-        rs: Option<HTTPRangeSpec>,
-        opts: &ObjectOptions,
-    ) -> Vec<u8> {
-        let headers = HeaderMap::new();
-        let (_, offset, length) =
-            GetObjectReader::new(Box::new(Cursor::new(Vec::new())), rs.clone(), &fixture.object_info, opts, &headers)
-                .await
-                .expect("plan compressed multipart read");
-
-        let end = offset + usize::try_from(length).expect("storage window length must be non-negative");
-        assert!(
-            end <= fixture.stored.len(),
-            "planned storage window {offset}..{end} exceeds stored stream of {} bytes",
-            fixture.stored.len()
-        );
-        let window = fixture.stored[offset..end].to_vec();
-
-        let (mut reader, replay_offset, replay_length) =
-            GetObjectReader::new(Box::new(Cursor::new(window)), rs, &fixture.object_info, opts, &headers)
-                .await
-                .expect("build compressed multipart reader");
-        assert_eq!((replay_offset, replay_length), (offset, length), "read plan must be deterministic");
-
-        reader.read_all().await.expect("read compressed multipart stream")
-    }
-
-    /// Byte pattern with a 2 KiB period: it compresses extremely well while
-    /// looking nothing like ASCII fixtures. Mirrors the e2e generator that
-    /// exposed a truncated full GET on high-ratio multipart payloads.
-    fn high_ratio_binary_payload(size: usize, seed: u8) -> Vec<u8> {
-        (0..size)
-            .map(|i| ((i as u64).wrapping_mul(2_654_435_761).wrapping_add(seed as u64) >> 3) as u8)
-            .collect()
-    }
-
-    #[tokio::test]
-    async fn compressed_multipart_full_get_handles_high_ratio_binary_payload() {
-        let part_sizes = [5 * 1024 * 1024_usize, 1024 * 1024];
-        let mut plaintext = Vec::new();
-        let mut stored = Vec::new();
-        let mut parts = Vec::with_capacity(part_sizes.len());
-
-        for (i, part_size) in part_sizes.iter().enumerate() {
-            let part_plaintext = high_ratio_binary_payload(*part_size, if i == 0 { 7 } else { 61 });
-            let (compressed, index) = compressed_part_fixture(&part_plaintext).await;
-            parts.push(ObjectPartInfo {
-                number: i + 1,
-                size: compressed.len(),
-                actual_size: *part_size as i64,
-                index,
-                ..Default::default()
-            });
-            stored.extend_from_slice(&compressed);
-            plaintext.extend_from_slice(&part_plaintext);
-        }
-
-        let mut user_defined = HashMap::new();
-        rustfs_utils::http::insert_str(
-            &mut user_defined,
-            rustfs_utils::http::SUFFIX_COMPRESSION,
-            crate::io_support::rio::compression_metadata_value(CompressionAlgorithm::default()),
-        );
-        rustfs_utils::http::insert_str(&mut user_defined, rustfs_utils::http::SUFFIX_ACTUAL_SIZE, plaintext.len().to_string());
-        let fixture = CompressedMultipartFixture {
-            object_info: ObjectInfo {
-                bucket: "test-bucket".to_string(),
-                name: "high-ratio-multipart".to_string(),
-                size: stored.len() as i64,
-                etag: Some("6bcf86bed8807b8e78f0fc6e0a53079d-2".to_string()),
-                parts: Arc::new(parts),
-                user_defined: Arc::new(user_defined),
-                ..Default::default()
-            },
-            stored,
-            plaintext,
-        };
-
-        let read = read_compressed_multipart(&fixture, None, &ObjectOptions::default()).await;
-
-        assert_eq!(read.len(), fixture.plaintext.len(), "full GET must return the logical size");
-        assert_eq!(read, fixture.plaintext, "high-ratio multipart payload must survive the roundtrip");
-    }
-
-    /// Full GET over a compressed multipart object must decode across part
-    /// boundaries: every part is an independent compressed stream (this is also
-    /// the on-disk shape written by builds before rustfs/rustfs#5169 disabled
-    /// multipart compression, so this pins legacy-object readability).
-    #[tokio::test]
-    async fn compressed_multipart_full_get_decodes_across_part_boundaries() {
-        let fixture = compressed_multipart_fixture(&[3 * 1024 * 1024, 2 * 1024 * 1024, 512 * 1024]).await;
-
-        let read = read_compressed_multipart(&fixture, None, &ObjectOptions::default()).await;
-
-        assert_eq!(read.len(), fixture.plaintext.len(), "full GET must return the logical size");
-        assert_eq!(read, fixture.plaintext, "full GET must reassemble all parts");
-    }
-
-    #[tokio::test]
-    async fn compressed_multipart_range_get_crosses_part_boundary() {
-        let fixture = compressed_multipart_fixture(&[3 * 1024 * 1024, 2 * 1024 * 1024]).await;
-        let boundary = 3 * 1024 * 1024_i64;
-        let rs = HTTPRangeSpec {
-            is_suffix_length: false,
-            start: boundary - 100_000,
-            end: boundary + 100_000 - 1,
-        };
-
-        let read = read_compressed_multipart(&fixture, Some(rs), &ObjectOptions::default()).await;
-
-        let expected = &fixture.plaintext[(boundary - 100_000) as usize..(boundary + 100_000) as usize];
-        assert_eq!(read, expected, "boundary-crossing range must splice both parts");
-    }
-
-    #[tokio::test]
-    async fn compressed_multipart_range_get_seeks_into_later_part() {
-        let fixture = compressed_multipart_fixture(&[3 * 1024 * 1024, 4 * 1024 * 1024]).await;
-        // Deep inside part 2 so the plan skips part 1 entirely and (when the
-        // part carries an index) seeks within part 2.
-        let start = 3 * 1024 * 1024_i64 + 2 * 1024 * 1024_i64 + 137;
-        let rs = HTTPRangeSpec {
-            is_suffix_length: false,
-            start,
-            end: start + 64 * 1024 - 1,
-        };
-
-        let read = read_compressed_multipart(&fixture, Some(rs), &ObjectOptions::default()).await;
-
-        let expected = &fixture.plaintext[start as usize..(start + 64 * 1024) as usize];
-        assert_eq!(read, expected, "range inside a later part must decode from that part");
-    }
-
-    /// Parts written without a compression index (small parts skip the index in
-    /// the rio-v2 backend) must still be rangeable: the plan starts at the part
-    /// boundary and skips decompressed bytes.
-    #[tokio::test]
-    async fn compressed_multipart_range_get_works_without_part_indexes() {
-        let mut fixture = compressed_multipart_fixture(&[1024 * 1024, 1024 * 1024]).await;
-        let parts = fixture
-            .object_info
-            .parts
-            .iter()
-            .map(|part| ObjectPartInfo {
-                index: None,
-                ..part.clone()
-            })
-            .collect::<Vec<_>>();
-        fixture.object_info.parts = Arc::new(parts);
-
-        let start = 1024 * 1024_i64 + 4096;
-        let rs = HTTPRangeSpec {
-            is_suffix_length: false,
-            start,
-            end: start + 32 * 1024 - 1,
-        };
-
-        let read = read_compressed_multipart(&fixture, Some(rs), &ObjectOptions::default()).await;
-
-        let expected = &fixture.plaintext[start as usize..(start + 32 * 1024) as usize];
-        assert_eq!(read, expected, "index-less parts must fall back to part-boundary skip");
-    }
-
-    #[tokio::test]
-    async fn compressed_multipart_part_number_get_returns_single_part() {
-        let part_sizes = [3 * 1024 * 1024, 2 * 1024 * 1024, 512 * 1024];
-        let fixture = compressed_multipart_fixture(&part_sizes).await;
-
-        let mut logical_offset = 0_usize;
-        for (i, part_size) in part_sizes.iter().enumerate() {
-            let opts = ObjectOptions {
-                part_number: Some(i + 1),
-                ..Default::default()
-            };
-
-            let read = read_compressed_multipart(&fixture, None, &opts).await;
-
-            let expected = &fixture.plaintext[logical_offset..logical_offset + part_size];
-            assert_eq!(read.len(), *part_size, "partNumber={} GET must return the part's logical size", i + 1);
-            assert_eq!(read, expected, "partNumber={} GET must return the original part bytes", i + 1);
-            logical_offset += part_size;
-        }
-    }
-
-    #[tokio::test]
-    async fn compressed_multipart_suffix_range_reads_tail() {
-        let fixture = compressed_multipart_fixture(&[3 * 1024 * 1024, 1024 * 1024]).await;
-        let suffix_len = 128 * 1024_i64;
-        let rs = HTTPRangeSpec {
-            is_suffix_length: true,
-            start: suffix_len,
-            end: -1,
-        };
-
-        let read = read_compressed_multipart(&fixture, Some(rs), &ObjectOptions::default()).await;
-
-        let expected = &fixture.plaintext[fixture.plaintext.len() - suffix_len as usize..];
-        assert_eq!(read, expected, "suffix range must return the tail of the last part");
-    }
-
-    /// Builds an SSE-C + disk-compression multipart object exactly like the
-    /// write path: each part is compressed into its own stream and then
-    /// encrypted with the per-part key schedule. The fixture is
-    /// legacy-encryption-specific (`rustfs_rio::EncryptReader`), matching the
-    /// pre-existing `build_legacy_ssec_multipart_fixture` shape, while the
-    /// compression layer follows the active backend feature.
-    async fn compressed_encrypted_multipart_fixture(key_bytes: [u8; 32], part_sizes: &[usize]) -> CompressedMultipartFixture {
-        let pattern = b"compressed encrypted multipart fixture data ";
-        let mut plaintext = Vec::new();
-        let mut stored = Vec::new();
-        let mut parts = Vec::with_capacity(part_sizes.len());
-
-        for (i, part_size) in part_sizes.iter().enumerate() {
-            let part_number = i + 1;
-            let mut part_plaintext = Vec::with_capacity(*part_size);
-            while part_plaintext.len() < *part_size {
-                part_plaintext.extend_from_slice(pattern);
-                part_plaintext.push(part_number as u8);
-            }
-            part_plaintext.truncate(*part_size);
-
-            let (compressed, index) = compressed_part_fixture(&part_plaintext).await;
-            let mut part_cipher = Vec::new();
-            rustfs_rio::EncryptReader::new_multipart(Cursor::new(compressed), key_bytes, LEGACY_FIXTURE_BASE_NONCE, part_number)
-                .read_to_end(&mut part_cipher)
-                .await
-                .expect("encrypt compressed fixture part");
-
-            parts.push(ObjectPartInfo {
-                number: part_number,
-                size: part_cipher.len(),
-                actual_size: *part_size as i64,
-                index,
-                ..Default::default()
-            });
-            stored.extend_from_slice(&part_cipher);
-            plaintext.extend_from_slice(&part_plaintext);
-        }
-
-        let mut user_defined = legacy_ssec_multipart_metadata(key_bytes, plaintext.len());
-        rustfs_utils::http::insert_str(
-            &mut user_defined,
-            rustfs_utils::http::SUFFIX_COMPRESSION,
-            crate::io_support::rio::compression_metadata_value(CompressionAlgorithm::default()),
-        );
-        rustfs_utils::http::insert_str(&mut user_defined, rustfs_utils::http::SUFFIX_ACTUAL_SIZE, plaintext.len().to_string());
-
-        let object_info = ObjectInfo {
-            bucket: "test-bucket".to_string(),
-            name: "compressed-encrypted-multipart".to_string(),
-            size: stored.len() as i64,
-            etag: Some(format!("6bcf86bed8807b8e78f0fc6e0a53079d-{}", part_sizes.len())),
-            parts: Arc::new(parts),
-            user_defined: Arc::new(user_defined),
-            ..Default::default()
-        };
-
-        CompressedMultipartFixture {
-            object_info,
-            stored,
-            plaintext,
-        }
-    }
-
-    async fn read_compressed_encrypted_multipart(
-        fixture: &CompressedMultipartFixture,
-        key_bytes: [u8; 32],
-        rs: Option<HTTPRangeSpec>,
-        opts: &ObjectOptions,
-    ) -> Vec<u8> {
-        let headers = ssec_headers_from_key(key_bytes);
-        let (_, offset, length) =
-            GetObjectReader::new(Box::new(Cursor::new(Vec::new())), rs.clone(), &fixture.object_info, opts, &headers)
-                .await
-                .expect("plan compressed encrypted multipart read");
-
-        let end = offset + usize::try_from(length).expect("storage window length must be non-negative");
-        assert!(
-            end <= fixture.stored.len(),
-            "planned storage window {offset}..{end} exceeds stored stream of {} bytes",
-            fixture.stored.len()
-        );
-        let window = fixture.stored[offset..end].to_vec();
-
-        let (mut reader, replay_offset, replay_length) =
-            GetObjectReader::new(Box::new(Cursor::new(window)), rs, &fixture.object_info, opts, &headers)
-                .await
-                .expect("build compressed encrypted multipart reader");
-        assert_eq!((replay_offset, replay_length), (offset, length), "read plan must be deterministic");
-
-        reader.read_all().await.expect("read compressed encrypted multipart stream")
-    }
-
-    #[tokio::test]
-    async fn compressed_encrypted_multipart_full_get_roundtrip() {
-        let key_bytes = [0x6Eu8; 32];
-        let fixture = compressed_encrypted_multipart_fixture(key_bytes, &[3 * 1024 * 1024, 1024 * 1024]).await;
-
-        let read = read_compressed_encrypted_multipart(&fixture, key_bytes, None, &ObjectOptions::default()).await;
-
-        assert_eq!(read.len(), fixture.plaintext.len(), "full GET must return the logical size");
-        assert_eq!(read, fixture.plaintext, "SSE-C + compression full GET must reassemble all parts");
-    }
-
-    #[tokio::test]
-    async fn compressed_encrypted_multipart_range_crosses_part_boundary() {
-        let key_bytes = [0x6Eu8; 32];
-        let fixture = compressed_encrypted_multipart_fixture(key_bytes, &[3 * 1024 * 1024, 1024 * 1024]).await;
-        let boundary = 3 * 1024 * 1024_i64;
-        let rs = HTTPRangeSpec {
-            is_suffix_length: false,
-            start: boundary - 65_536,
-            end: boundary + 65_536 - 1,
-        };
-
-        let read = read_compressed_encrypted_multipart(&fixture, key_bytes, Some(rs), &ObjectOptions::default()).await;
-
-        let expected = &fixture.plaintext[(boundary - 65_536) as usize..(boundary + 65_536) as usize];
-        assert_eq!(read, expected, "SSE-C + compression boundary-crossing range must splice both parts");
-    }
-
-    #[tokio::test]
-    async fn compressed_encrypted_multipart_part_number_get_returns_single_part() {
-        let key_bytes = [0x6Eu8; 32];
-        let part_sizes = [3 * 1024 * 1024, 1024 * 1024];
-        let fixture = compressed_encrypted_multipart_fixture(key_bytes, &part_sizes).await;
-
-        let opts = ObjectOptions {
-            part_number: Some(2),
-            ..Default::default()
-        };
-        let read = read_compressed_encrypted_multipart(&fixture, key_bytes, None, &opts).await;
-
-        let expected = &fixture.plaintext[part_sizes[0]..];
-        assert_eq!(read.len(), part_sizes[1], "partNumber=2 GET must return the part's logical size");
-        assert_eq!(read, expected, "partNumber=2 GET must return the original part bytes");
-    }
-
    #[tokio::test]
    async fn test_get_object_reader_rejects_ssec_read_without_headers() {
        let object_info = ObjectInfo {
@@ -172,7 +172,6 @@ impl ObjectLockConfigSnapshot {
        }
    }

-    #[allow(dead_code, reason = "snapshot-scope predicate asserted by this file's tests (backlog#1823)")]
    pub(crate) fn is_for_store_bucket(
        &self,
        store_id: Uuid,
@@ -261,9 +260,6 @@ pub struct ObjectOptions {

    pub data_movement: bool,
    pub raw_data_movement_read: bool,
-    /// Materialize the data-movement per-part checksum sidecar for APIs that
-    /// return part checksums. Ordinary object reads leave it encoded.
-    pub include_part_checksums: bool,
    pub src_pool_idx: usize,
    pub user_defined: HashMap<String, String>,
    pub preserve_etag: Option<String>,
@@ -31,6 +31,7 @@ use std::{
 use tokio::sync::{OnceCell, RwLock};
 use tokio_util::sync::CancellationToken;
 use tracing::warn;
+use uuid::Uuid;

 pub const DISK_ASSUME_UNKNOWN_SIZE: u64 = 1 << 30;
 pub const DISK_MIN_INODES: u64 = 1000;
@@ -108,6 +109,18 @@ pub fn set_global_rustfs_port(value: u16) {
    }
 }

+/// Set the global deployment id
+///
+/// # Arguments
+/// * `id` - The Uuid to set as the global deployment id
+///
+/// # Returns
+/// * None
+///
+pub fn set_global_deployment_id(id: Uuid) {
+    current_ctx().set_deployment_id(id);
+}
+
 /// Get the global deployment id
 ///
 /// # Returns
@@ -275,6 +288,19 @@ pub fn get_global_region() -> Option<s3s::region::Region> {
    current_ctx().region()
 }

+/// Initialize the global background services cancellation token
+///
+/// # Arguments
+/// * `cancel_token` - The CancellationToken instance to set globally
+///
+/// # Returns
+/// * `Ok(())` if successful
+/// * `Err(CancellationToken)` if setting fails
+///
+pub fn init_background_services_cancel_token(cancel_token: CancellationToken) -> Result<(), CancellationToken> {
+    current_ctx().init_background_cancel_token(cancel_token)
+}
+
 /// Get the global background services cancellation token
 ///
 /// # Returns
@@ -284,6 +310,18 @@ pub fn get_background_services_cancel_token() -> Option<CancellationToken> {
    current_ctx().background_cancel_token()
 }

+/// Create and initialize the global background services cancellation token
+///
+/// # Returns
+/// * `CancellationToken` - The newly created global cancellation token
+///
+pub fn create_background_services_cancel_token() -> CancellationToken {
+    let cancel_token = CancellationToken::new();
+    init_background_services_cancel_token(cancel_token.clone())
+        .expect("background services cancel token should be initialized once during startup");
+    cancel_token
+}
+
 /// Shutdown all background services gracefully
 ///
 /// # Returns
@@ -402,10 +402,6 @@ impl InstanceContext {
    }

    #[cfg(test)]
-    #[allow(
-        dead_code,
-        reason = "driven by the tier-delete-journal recovery test behind `--features test-util` (backlog#1823)"
-    )]
    pub(crate) fn wake_tier_delete_journal_recovery(&self) {
        self.tier_delete_journal_recovery_wakeup.notify_one();
    }
@@ -13,6 +13,7 @@
 // limitations under the License.

 // #730: runtime source migration keeps fallback handles until all owners inject state.
+#![allow(dead_code)]

 pub(crate) mod global;
 pub(crate) mod instance;
@@ -38,6 +38,7 @@ use crate::{
        set_object_layer, update_erasure_type,
    },
    services::batch_processor::{GlobalBatchProcessors, get_global_processors},
+    services::event_notification::EventNotifier,
    services::notification_sys::{NotificationSys, get_global_notification_sys},
    services::tier::tier::TierConfigMgr,
    store::ECStore,
@@ -142,10 +143,6 @@ pub async fn setup_is_erasure_sd() -> bool {
    is_erasure_sd().await
 }

-#[allow(
-    dead_code,
-    reason = "setup-type override used only by tests across this crate (backlog#1823)"
-)]
 pub(crate) async fn current_setup_type() -> SetupType {
    if setup_is_dist_erasure().await {
        SetupType::DistErasure
@@ -158,10 +155,6 @@ pub(crate) async fn current_setup_type() -> SetupType {
    }
 }

-#[allow(
-    dead_code,
-    reason = "setup-type override used only by tests across this crate (backlog#1823)"
-)]
 pub(crate) async fn set_setup_type(setup_type: SetupType) {
    update_erasure_type(setup_type).await;
 }
@@ -171,9 +164,6 @@ pub(crate) async fn local_node_name() -> String {
 }

 pub(crate) async fn set_local_node_name(node_name: String) {
-    // Also stamp the internode-metrics server label: io-metrics is a leaf
-    // crate and no longer resolves node identity itself (backlog#1834).
-    rustfs_io_metrics::internode_metrics::set_internode_server_label(node_name.as_str());
    rustfs_common::set_global_local_node_name(&node_name).await;
 }

@@ -239,6 +229,14 @@ pub(crate) fn ensure_test_rpc_secret() {
    let _ = rustfs_credentials::set_global_rpc_secret(TEST_RPC_SECRET.to_owned());
 }

+pub(crate) fn storage_class_parity(storage_class: Option<&str>) -> Option<usize> {
+    get_global_storage_class_snapshot().get_parity_for_sc(storage_class.unwrap_or_default())
+}
+
+pub(crate) fn storage_class_should_inline(shard_size: i64, versioned: bool) -> bool {
+    get_global_storage_class_snapshot().should_inline(shard_size, versioned)
+}
+
 pub(crate) fn deployment_upload_id(upload_id: &str) -> String {
    base64_simd::URL_SAFE_NO_PAD
        .encode_to_string(format!("{}.{}", get_global_deployment_id().unwrap_or_default(), upload_id).as_bytes())
@@ -331,6 +329,21 @@ pub(crate) fn storage_class_config_snapshot() -> Arc<storageclass::Config> {
    get_global_storage_class_snapshot()
 }

+/// Scalar STANDARD / RRS parity for backend-info reporting.
+///
+/// Retained for the rebalance/backend-info path. `get_parity_for_sc` returns
+/// `None` when the runtime config is uninitialized or (post per-pool support)
+/// when pools disagree, so STANDARD falls back to the caller's default and RRS
+/// stays `None` — matching the pre-per-pool scalar reporting.
+pub(crate) fn backend_storage_class_parities(default_standard_parity: usize) -> (Option<usize>, Option<usize>) {
+    let sc = get_global_storage_class_snapshot();
+    let standard = sc
+        .get_parity_for_sc(storageclass::CLASS_STANDARD)
+        .or(Some(default_standard_parity));
+    let reduced_redundancy = sc.get_parity_for_sc(storageclass::RRS);
+    (standard, reduced_redundancy)
+}
+
 pub(crate) fn set_storage_class_config(config: storageclass::Config) {
    set_global_storage_class(config);
 }
@@ -398,6 +411,10 @@ pub fn transition_state_handle() -> Arc<TransitionState> {
    crate::runtime::global::current_ctx().transition_state()
 }

+pub(crate) fn event_notifier_handle() -> Arc<RwLock<EventNotifier>> {
+    crate::runtime::global::current_ctx().event_notifier()
+}
+
 pub(crate) async fn local_disk_by_path(path: &str) -> Option<DiskStore> {
    local_disk_map_handle().read().await.get(path).cloned().flatten()
 }
@@ -491,6 +508,30 @@ pub(crate) async fn local_disk_set_drive(
    instance_ctx.local_disk_set_drives().read().await[pool_idx][set_idx][disk_idx].clone()
 }

+pub(crate) async fn local_disk_for_endpoint(endpoint: &Endpoint) -> Option<DiskStore> {
+    let set_drives = local_disk_set_drives_handle();
+    let global_set_drives = set_drives.read().await;
+    if global_set_drives.is_empty() {
+        return local_disk_map_handle()
+            .read()
+            .await
+            .get(&endpoint.to_string())
+            .cloned()
+            .unwrap_or(None);
+    }
+
+    let pool_idx = usize::try_from(endpoint.pool_idx).ok()?;
+    let set_idx = usize::try_from(endpoint.set_idx).ok()?;
+    let disk_idx = usize::try_from(endpoint.disk_idx).ok()?;
+
+    global_set_drives
+        .get(pool_idx)
+        .and_then(|sets| sets.get(set_idx))
+        .and_then(|disks| disks.get(disk_idx))
+        .cloned()
+        .unwrap_or(None)
+}
+
 pub(crate) async fn local_disk_paths() -> Vec<String> {
    local_disk_map_handle().read().await.keys().cloned().collect()
 }
@@ -23,10 +23,6 @@ use std::sync::{Arc, Mutex};
 use std::time::{Duration, Instant};
 use tokio::task::JoinSet;

-#[allow(
-    dead_code,
-    reason = "default operation label for the test-only AsyncBatchProcessor::new (backlog#1823)"
-)]
 const BATCH_PROCESSOR_OPERATION_CUSTOM: &str = "custom";
 const BATCH_PROCESSOR_OPERATION_READ: &str = "read";
 const BATCH_PROCESSOR_OPERATION_WRITE: &str = "write";
@@ -215,7 +211,6 @@ pub struct AsyncBatchProcessor {
 }

 impl AsyncBatchProcessor {
-    #[allow(dead_code, reason = "constructor used only by this file's tests (backlog#1823)")]
    pub fn new(max_concurrent: usize) -> Self {
        Self::new_with_operation(max_concurrent, BATCH_PROCESSOR_OPERATION_CUSTOM)
    }
@@ -26,26 +26,11 @@ use std::sync::atomic::Ordering;
 use tokio::sync::RwLock;
 use tracing::warn;

-/// Dead ecstore-side notification skeleton.
-///
-/// The working notification stack is `rustfs-notify`, whose own `EventNotifier`
-/// is the one bucket configuration actually drives. Nothing calls the methods
-/// below; `init_bucket_targets` even logs that it is a no-op in this build.
-/// Removing it means also retiring the `InstanceContext` slot that holds it
-/// (backlog#939 Phase 5), so it is left explicit here rather than half-removed.
-#[allow(
-    dead_code,
-    reason = "ecstore-side notification skeleton superseded by rustfs-notify; see module note (backlog#1823)"
-)]
 pub struct EventNotifier {
    target_list: TargetList,
    //bucket_rules_map: HashMap<String , HashMap<EventName, Rules>>,
 }

-#[allow(
-    dead_code,
-    reason = "ecstore-side notification skeleton superseded by rustfs-notify; see module note (backlog#1823)"
-)]
 impl EventNotifier {
    pub fn new() -> Arc<RwLock<Self>> {
        Arc::new(RwLock::new(Self {
@@ -13,6 +13,7 @@
 // limitations under the License.

 // #730: background service owners still contain staged notification/rebalance/tier paths.
+#![allow(dead_code)]

 pub(crate) mod batch_processor;
 pub(crate) mod event_notification;
@@ -44,14 +44,12 @@ const CONSECUTIVE_FAILURE_THRESHOLD: u32 = 3;
 const LOG_COMPONENT_ECSTORE: &str = "ecstore";
 const LOG_SUBSYSTEM_NOTIFICATION: &str = "notification";
 const EVENT_NOTIFICATION_PEER_PROPAGATION: &str = "notification_peer_propagation";
-const EVENT_NOTIFICATION_CAPABILITY_PROBE: &str = "notification_capability_probe";
 const SCANNER_ACTIVITY_PROBE_TIMEOUT: Duration = Duration::from_secs(5);
 const TIER_CONFIG_RELOAD_RETRY_BASE: Duration = Duration::from_millis(100);
 const TIER_CONFIG_RELOAD_RETRY_CAP: Duration = Duration::from_secs(5);
 const REMOTE_VERSION_STATE_PROBE_INTERVAL: Duration = Duration::from_secs(10);
 const REMOTE_VERSION_STATE_PROBE_TIMEOUT: Duration = Duration::from_secs(5);
 const REMOTE_VERSION_STATE_PROOF_TTL: Duration = Duration::from_secs(30);
-const CROSS_POOL_FENCE_SUPPORTED_VERSION: u32 = 1;

 /// Cached result from the last successful admin call to a peer.
 struct PeerAdminCache {
@@ -97,15 +95,15 @@ lazy_static! {
 }

 #[derive(Clone)]
-struct FleetCapabilityProof {
+struct RemoteVersionStateFleetProof {
    topology_fingerprint: String,
    peer_epochs: Arc<BTreeMap<String, Uuid>>,
    expires_at: Instant,
 }

-impl FleetCapabilityProof {
-    fn token(&self) -> FleetCapabilityProofToken {
-        FleetCapabilityProofToken {
+impl RemoteVersionStateFleetProof {
+    fn token(&self) -> RemoteVersionStateFleetProofToken {
+        RemoteVersionStateFleetProofToken {
            topology_fingerprint: self.topology_fingerprint.clone(),
            peer_epochs: self.peer_epochs.clone(),
        }
@@ -113,41 +111,37 @@ impl FleetCapabilityProof {
 }

 #[derive(Clone, PartialEq, Eq)]
-struct FleetCapabilityProofToken {
+pub(crate) struct RemoteVersionStateFleetProofToken {
    topology_fingerprint: String,
    peer_epochs: Arc<BTreeMap<String, Uuid>>,
 }

 #[derive(Default)]
-struct FleetCapabilityProofState {
-    proof: Option<FleetCapabilityProof>,
+struct RemoteVersionStateFleetProofState {
+    proof: Option<RemoteVersionStateFleetProof>,
    topology_conflict: bool,
 }

-#[derive(Clone, PartialEq, Eq)]
-pub(crate) struct RemoteVersionStateFleetProofToken(FleetCapabilityProofToken);
-
-#[derive(Clone, PartialEq, Eq)]
-pub struct CrossPoolFenceFleetProofToken(FleetCapabilityProofToken);
-
-static REMOTE_VERSION_STATE_FLEET_PROOF: OnceLock<std::sync::RwLock<FleetCapabilityProofState>> = OnceLock::new();
-static CROSS_POOL_FENCE_FLEET_PROOF: OnceLock<std::sync::RwLock<FleetCapabilityProofState>> = OnceLock::new();
+static REMOTE_VERSION_STATE_FLEET_PROOF: OnceLock<std::sync::RwLock<RemoteVersionStateFleetProofState>> = OnceLock::new();
 static REMOTE_VERSION_STATE_PROBE_TOPOLOGY: OnceLock<String> = OnceLock::new();

-fn cross_pool_fence_fleet_proof_slot() -> &'static std::sync::RwLock<FleetCapabilityProofState> {
-    CROSS_POOL_FENCE_FLEET_PROOF.get_or_init(|| std::sync::RwLock::new(FleetCapabilityProofState::default()))
+fn remote_version_state_fleet_proof_slot() -> &'static std::sync::RwLock<RemoteVersionStateFleetProofState> {
+    REMOTE_VERSION_STATE_FLEET_PROOF.get_or_init(|| std::sync::RwLock::new(RemoteVersionStateFleetProofState::default()))
 }

-fn remote_version_state_fleet_proof_slot() -> &'static std::sync::RwLock<FleetCapabilityProofState> {
-    REMOTE_VERSION_STATE_FLEET_PROOF.get_or_init(|| std::sync::RwLock::new(FleetCapabilityProofState::default()))
+fn replace_remote_version_state_fleet_proof(proof: Option<RemoteVersionStateFleetProof>) {
+    replace_remote_version_state_fleet_proof_in(remote_version_state_fleet_proof_slot(), proof);
 }

-fn replace_fleet_capability_proof(slot: &std::sync::RwLock<FleetCapabilityProofState>, proof: Option<FleetCapabilityProof>) {
+fn replace_remote_version_state_fleet_proof_in(
+    slot: &std::sync::RwLock<RemoteVersionStateFleetProofState>,
+    proof: Option<RemoteVersionStateFleetProof>,
+) {
    slot.write().unwrap_or_else(std::sync::PoisonError::into_inner).proof = proof;
 }

-fn publish_fleet_capability_probe_result(
-    slot: &std::sync::RwLock<FleetCapabilityProofState>,
+fn publish_remote_version_state_probe_result(
+    slot: &std::sync::RwLock<RemoteVersionStateFleetProofState>,
    topology_fingerprint: &str,
    result: Result<BTreeMap<String, Uuid>>,
    observed_at: Instant,
@@ -161,7 +155,7 @@ fn publish_fleet_capability_probe_result(
                .filter(|proof| proof.topology_fingerprint == topology_fingerprint && proof.peer_epochs.as_ref() == &peer_epochs)
                .map(|proof| Arc::clone(&proof.peer_epochs))
                .unwrap_or_else(|| Arc::new(peer_epochs));
-            state.proof = Some(FleetCapabilityProof {
+            state.proof = Some(RemoteVersionStateFleetProof {
                topology_fingerprint: topology_fingerprint.to_string(),
                peer_epochs,
                expires_at: observed_at + REMOTE_VERSION_STATE_PROOF_TTL,
@@ -169,7 +163,7 @@ fn publish_fleet_capability_probe_result(
            None
        }
        Err(err) => {
-            replace_fleet_capability_proof(slot, None);
+            replace_remote_version_state_fleet_proof_in(slot, None);
            Some(err)
        }
    }
@@ -180,60 +174,27 @@ pub(crate) fn acquire_remote_version_state_fleet_proof() -> Option<RemoteVersion
    let state = remote_version_state_fleet_proof_slot()
        .read()
        .unwrap_or_else(std::sync::PoisonError::into_inner);
-    acquire_fleet_capability_proof_from(&state, expected_topology, Instant::now()).map(RemoteVersionStateFleetProofToken)
+    acquire_remote_version_state_fleet_proof_from(&state, expected_topology, Instant::now())
 }

-fn acquire_fleet_capability_proof_from(
-    state: &FleetCapabilityProofState,
+fn acquire_remote_version_state_fleet_proof_from(
+    state: &RemoteVersionStateFleetProofState,
    expected_topology: &str,
    now: Instant,
-) -> Option<FleetCapabilityProofToken> {
-    if state.topology_conflict || !fleet_capability_proof_valid_at(state.proof.as_ref(), expected_topology, now) {
+) -> Option<RemoteVersionStateFleetProofToken> {
+    if state.topology_conflict || !remote_version_state_fleet_proof_valid_at(state.proof.as_ref(), expected_topology, now) {
        return None;
    }
-    state.proof.as_ref().map(FleetCapabilityProof::token)
+    state.proof.as_ref().map(RemoteVersionStateFleetProof::token)
 }

 pub(crate) fn remote_version_state_fleet_proof_matches(proof: &RemoteVersionStateFleetProofToken) -> bool {
-    fleet_capability_proof_matches(remote_version_state_fleet_proof_slot(), &proof.0)
-}
-
-pub fn acquire_cross_pool_fence_fleet_proof() -> Option<CrossPoolFenceFleetProofToken> {
-    let expected_topology = REMOTE_VERSION_STATE_PROBE_TOPOLOGY.get()?;
-    let state = cross_pool_fence_fleet_proof_slot()
-        .read()
-        .unwrap_or_else(std::sync::PoisonError::into_inner);
-    acquire_fleet_capability_proof_from(&state, expected_topology, Instant::now()).map(CrossPoolFenceFleetProofToken)
-}
-
-pub fn cross_pool_fence_fleet_proof_matches(proof: &CrossPoolFenceFleetProofToken) -> bool {
-    fleet_capability_proof_matches(cross_pool_fence_fleet_proof_slot(), &proof.0)
-}
-
-#[cfg(any(test, feature = "test-util"))]
-pub fn rotate_cross_pool_fence_fleet_proof_for_test() -> bool {
-    let mut state = cross_pool_fence_fleet_proof_slot()
-        .write()
-        .unwrap_or_else(std::sync::PoisonError::into_inner);
-    let Some(current) = state.proof.as_ref() else {
-        return false;
-    };
-    state.proof = Some(FleetCapabilityProof {
-        topology_fingerprint: current.topology_fingerprint.clone(),
-        peer_epochs: Arc::new(current.peer_epochs.as_ref().clone()),
-        expires_at: current.expires_at,
-    });
-    true
-}
-
-fn fleet_capability_proof_matches(
-    slot: &std::sync::RwLock<FleetCapabilityProofState>,
-    proof: &FleetCapabilityProofToken,
-) -> bool {
    let Some(expected_topology) = REMOTE_VERSION_STATE_PROBE_TOPOLOGY.get() else {
        return false;
    };
-    let state = slot.read().unwrap_or_else(std::sync::PoisonError::into_inner);
+    let state = remote_version_state_fleet_proof_slot()
+        .read()
+        .unwrap_or_else(std::sync::PoisonError::into_inner);
    if state.topology_conflict {
        return false;
    }
@@ -245,42 +206,14 @@ fn fleet_capability_proof_matches(
    })
 }

-fn fleet_capability_proof_valid_at(proof: Option<&FleetCapabilityProof>, expected_topology: &str, now: Instant) -> bool {
+fn remote_version_state_fleet_proof_valid_at(
+    proof: Option<&RemoteVersionStateFleetProof>,
+    expected_topology: &str,
+    now: Instant,
+) -> bool {
    proof.is_some_and(|proof| proof.topology_fingerprint == expected_topology && now < proof.expires_at)
 }

-#[cfg(test)]
-pub(crate) struct RemoteVersionStateFleetProofGuard;
-
-#[cfg(test)]
-impl Drop for RemoteVersionStateFleetProofGuard {
-    fn drop(&mut self) {
-        replace_fleet_capability_proof(remote_version_state_fleet_proof_slot(), None);
-    }
-}
-
-#[cfg(test)]
-pub(crate) fn install_remote_version_state_fleet_proof_for_test(topology_fingerprint: &str) -> RemoteVersionStateFleetProofGuard {
-    match REMOTE_VERSION_STATE_PROBE_TOPOLOGY.set(topology_fingerprint.to_string()) {
-        Ok(()) => {}
-        Err(_)
-            if REMOTE_VERSION_STATE_PROBE_TOPOLOGY
-                .get()
-                .is_some_and(|current| current == topology_fingerprint) => {}
-        Err(_) => panic!("remote version state test topology is already bound to another fingerprint"),
-    }
-    let peer_epochs = BTreeMap::new();
-    if let Some(err) = publish_fleet_capability_probe_result(
-        remote_version_state_fleet_proof_slot(),
-        topology_fingerprint,
-        Ok(peer_epochs),
-        Instant::now(),
-    ) {
-        panic!("test proof installation must not fail: {err}");
-    }
-    RemoteVersionStateFleetProofGuard
-}
-
 fn insert_remote_version_state_peer(peer_epochs: &mut BTreeMap<String, Uuid>, peer: String, epoch: Uuid) -> Result<()> {
    if epoch.is_nil() || peer_epochs.values().any(|existing| *existing == epoch) || peer_epochs.insert(peer, epoch).is_some() {
        return Err(Error::other("remote version state capability peer identity is invalid"));
@@ -291,11 +224,11 @@ fn insert_remote_version_state_peer(peer_epochs: &mut BTreeMap<String, Uuid>, pe
 pub fn start_remote_version_state_fleet_probe(topology_fingerprint: String) {
    if REMOTE_VERSION_STATE_PROBE_TOPOLOGY.set(topology_fingerprint.clone()).is_err() {
        if REMOTE_VERSION_STATE_PROBE_TOPOLOGY.get() != Some(&topology_fingerprint) {
-            for slot in [remote_version_state_fleet_proof_slot(), cross_pool_fence_fleet_proof_slot()] {
-                let mut state = slot.write().unwrap_or_else(std::sync::PoisonError::into_inner);
-                state.topology_conflict = true;
-                state.proof = None;
-            }
+            let mut state = remote_version_state_fleet_proof_slot()
+                .write()
+                .unwrap_or_else(std::sync::PoisonError::into_inner);
+            state.topology_conflict = true;
+            state.proof = None;
        }
        return;
    }
@@ -316,23 +249,13 @@ pub fn start_remote_version_state_fleet_probe(topology_fingerprint: String) {
                }
                None => Err(Error::other("remote version state fleet capability notification system is unavailable")),
            };
-            let fence_result = match get_global_notification_sys() {
-                Some(notification_sys) => timeout(
-                    REMOTE_VERSION_STATE_PROBE_TIMEOUT,
-                    notification_sys.probe_cross_pool_fence_fleet(&topology_fingerprint),
-                )
-                .await
-                .unwrap_or_else(|_| Err(Error::other("cross-pool fence fleet capability probe timed out"))),
-                None => Err(Error::other("cross-pool fence fleet capability notification system is unavailable")),
-            };
            let topology_conflict = remote_version_state_fleet_proof_slot()
                .read()
                .unwrap_or_else(std::sync::PoisonError::into_inner)
                .topology_conflict;
            if topology_conflict {
-                replace_fleet_capability_proof(remote_version_state_fleet_proof_slot(), None);
-                replace_fleet_capability_proof(cross_pool_fence_fleet_proof_slot(), None);
-            } else if let Some(err) = publish_fleet_capability_probe_result(
+                replace_remote_version_state_fleet_proof(None);
+            } else if let Some(err) = publish_remote_version_state_probe_result(
                remote_version_state_fleet_proof_slot(),
                &topology_fingerprint,
                result,
@@ -340,24 +263,6 @@ pub fn start_remote_version_state_fleet_probe(topology_fingerprint: String) {
            ) {
                debug!(error = %err, "remote version state fleet capability probe failed closed");
            }
-            if !topology_conflict
-                && let Some(err) = publish_fleet_capability_probe_result(
-                    cross_pool_fence_fleet_proof_slot(),
-                    &topology_fingerprint,
-                    fence_result,
-                    Instant::now(),
-                )
-            {
-                debug!(
-                    event = EVENT_NOTIFICATION_CAPABILITY_PROBE,
-                    component = LOG_COMPONENT_ECSTORE,
-                    subsystem = LOG_SUBSYSTEM_NOTIFICATION,
-                    capability = "cross_pool_fence_v1",
-                    state = "failed_closed",
-                    error = %err,
-                    "notification capability probe"
-                );
-            }
            sleep(REMOTE_VERSION_STATE_PROBE_INTERVAL).await;
        }
    });
@@ -425,27 +330,6 @@ impl NotificationSys {
        }
        Ok(peer_epochs)
    }
-
-    async fn probe_cross_pool_fence_fleet(&self, topology_fingerprint: &str) -> Result<BTreeMap<String, Uuid>> {
-        if self.peer_clients.len() != self.peer_topology_hosts.len() {
-            return Err(Error::other("cross-pool fence capability fleet membership is incomplete"));
-        }
-        let probes = self.peer_clients.iter().map(|client| async {
-            let client = client
-                .as_ref()
-                .ok_or_else(|| Error::other("cross-pool fence capability peer is unreachable"))?;
-            client.probe_cross_pool_fence(topology_fingerprint.to_string()).await
-        });
-        let mut peer_epochs = BTreeMap::new();
-        for result in join_all(probes).await {
-            let (peer, version, epoch) = result?;
-            if version < CROSS_POOL_FENCE_SUPPORTED_VERSION {
-                return Err(Error::other("cross-pool fence capability version is unsupported"));
-            }
-            insert_remote_version_state_peer(&mut peer_epochs, peer, epoch)?;
-        }
-        Ok(peer_epochs)
-    }
 }

 pub struct NotificationPeerErr {
@@ -1623,7 +1507,6 @@ impl NotificationSys {
        workers.peers.remove(host);
    }

-    #[allow(dead_code, reason = "asserted by this file's tests (backlog#1823)")]
    fn tier_config_reload_worker_active(&self, host: &str) -> bool {
        self.tier_config_reload_workers
            .lock()
@@ -1797,7 +1680,6 @@ where
        .map_err(|_| Error::other(format!("scanner activity peer {host} timed out after {timeout_duration:?}")))?
 }

-#[allow(dead_code, reason = "asserted by this file's tests (backlog#1823)")]
 async fn call_peer_with_timeout<F, Fut>(
    timeout_dur: Duration,
    host_label: &str,
@@ -2263,16 +2145,16 @@ mod tests {
        let now = Instant::now();
        let mut peer_epochs = BTreeMap::new();
        peer_epochs.insert("peer-a".to_string(), Uuid::new_v4());
-        let proof = FleetCapabilityProof {
+        let proof = RemoteVersionStateFleetProof {
            topology_fingerprint: "topology-a".to_string(),
            peer_epochs: Arc::new(peer_epochs),
            expires_at: now + Duration::from_secs(1),
        };

-        assert!(fleet_capability_proof_valid_at(Some(&proof), "topology-a", now));
-        assert!(!fleet_capability_proof_valid_at(Some(&proof), "topology-b", now));
-        assert!(!fleet_capability_proof_valid_at(Some(&proof), "topology-a", proof.expires_at));
-        assert!(!fleet_capability_proof_valid_at(None, "topology-a", now));
+        assert!(remote_version_state_fleet_proof_valid_at(Some(&proof), "topology-a", now));
+        assert!(!remote_version_state_fleet_proof_valid_at(Some(&proof), "topology-b", now));
+        assert!(!remote_version_state_fleet_proof_valid_at(Some(&proof), "topology-a", proof.expires_at));
+        assert!(!remote_version_state_fleet_proof_valid_at(None, "topology-a", now));
    }

    #[test]
@@ -2286,25 +2168,25 @@ mod tests {
    #[test]
    fn remote_version_state_fleet_proof_accepts_single_node_membership() {
        let now = Instant::now();
-        let proof = FleetCapabilityProof {
+        let proof = RemoteVersionStateFleetProof {
            topology_fingerprint: "topology-a".to_string(),
            peer_epochs: Arc::new(BTreeMap::new()),
            expires_at: now + Duration::from_secs(1),
        };

-        assert!(fleet_capability_proof_valid_at(Some(&proof), "topology-a", now));
+        assert!(remote_version_state_fleet_proof_valid_at(Some(&proof), "topology-a", now));
    }

    #[test]
    fn remote_version_state_fleet_proof_token_changes_with_process_epoch() {
        let now = Instant::now();
-        let proof = FleetCapabilityProof {
+        let proof = RemoteVersionStateFleetProof {
            topology_fingerprint: "topology-a".to_string(),
            peer_epochs: Arc::new(BTreeMap::from([("peer-a".to_string(), Uuid::new_v4())])),
            expires_at: now + Duration::from_secs(1),
        };
        let captured = proof.token();
-        let restarted = FleetCapabilityProof {
+        let restarted = RemoteVersionStateFleetProof {
            topology_fingerprint: proof.topology_fingerprint.clone(),
            peer_epochs: Arc::new(BTreeMap::from([("peer-a".to_string(), Uuid::new_v4())])),
            expires_at: proof.expires_at,
@@ -2315,11 +2197,11 @@ mod tests {

    #[test]
    fn remote_version_state_fleet_proof_renewal_preserves_only_same_epoch_token() {
-        let slot = std::sync::RwLock::new(FleetCapabilityProofState::default());
+        let slot = std::sync::RwLock::new(RemoteVersionStateFleetProofState::default());
        let now = Instant::now();
        let epoch = Uuid::new_v4();
        let peers = BTreeMap::from([("peer-a".to_string(), epoch)]);
-        assert!(publish_fleet_capability_probe_result(&slot, "topology-a", Ok(peers.clone()), now).is_none());
+        assert!(publish_remote_version_state_probe_result(&slot, "topology-a", Ok(peers.clone()), now).is_none());
        let original = slot
            .read()
            .expect("proof slot should not poison")
@@ -2328,7 +2210,9 @@ mod tests {
            .expect("successful probe should publish proof")
            .token();

-        assert!(publish_fleet_capability_probe_result(&slot, "topology-a", Ok(peers), now + Duration::from_millis(1)).is_none());
+        assert!(
+            publish_remote_version_state_probe_result(&slot, "topology-a", Ok(peers), now + Duration::from_millis(1)).is_none()
+        );
        let renewed = slot
            .read()
            .expect("proof slot should not poison")
@@ -2340,7 +2224,8 @@ mod tests {

        let restarted = BTreeMap::from([("peer-a".to_string(), Uuid::new_v4())]);
        assert!(
-            publish_fleet_capability_probe_result(&slot, "topology-a", Ok(restarted), now + Duration::from_millis(2)).is_none()
+            publish_remote_version_state_probe_result(&slot, "topology-a", Ok(restarted), now + Duration::from_millis(2))
+                .is_none()
        );
        let replaced = slot
            .read()
@@ -2355,18 +2240,18 @@ mod tests {
    #[test]
    fn remote_version_state_fleet_proof_conflict_revokes_atomic_snapshot() {
        let now = Instant::now();
-        let mut state = FleetCapabilityProofState {
-            proof: Some(FleetCapabilityProof {
+        let mut state = RemoteVersionStateFleetProofState {
+            proof: Some(RemoteVersionStateFleetProof {
                topology_fingerprint: "topology-a".to_string(),
                peer_epochs: Arc::new(BTreeMap::new()),
                expires_at: now + Duration::from_secs(1),
            }),
            topology_conflict: false,
        };
-        assert!(acquire_fleet_capability_proof_from(&state, "topology-a", now).is_some());
+        assert!(acquire_remote_version_state_fleet_proof_from(&state, "topology-a", now).is_some());

        state.topology_conflict = true;
-        assert!(acquire_fleet_capability_proof_from(&state, "topology-a", now).is_none());
+        assert!(acquire_remote_version_state_fleet_proof_from(&state, "topology-a", now).is_none());
    }

    #[test]
@@ -2382,19 +2267,19 @@ mod tests {

    #[test]
    fn remote_version_state_fleet_probe_failure_revokes_previous_proof() {
-        let slot = std::sync::RwLock::new(FleetCapabilityProofState::default());
+        let slot = std::sync::RwLock::new(RemoteVersionStateFleetProofState::default());
        let now = Instant::now();
        let peer_epochs = BTreeMap::from([("node-a:9000".to_string(), Uuid::new_v4())]);
-        assert!(publish_fleet_capability_probe_result(&slot, "topology-a", Ok(peer_epochs), now).is_none());
+        assert!(publish_remote_version_state_probe_result(&slot, "topology-a", Ok(peer_epochs), now).is_none());
        assert!(slot.read().expect("proof slot should not poison").proof.is_some());

        assert!(
-            publish_fleet_capability_probe_result(&slot, "topology-a", Err(Error::other("peer unavailable")), now,).is_some()
+            publish_remote_version_state_probe_result(&slot, "topology-a", Err(Error::other("peer unavailable")), now,).is_some()
        );
        assert!(slot.read().expect("proof slot should not poison").proof.is_none());

        let peer_epochs = BTreeMap::from([("node-a:9000".to_string(), Uuid::new_v4())]);
-        assert!(publish_fleet_capability_probe_result(&slot, "topology-a", Ok(peer_epochs), now).is_none());
+        assert!(publish_remote_version_state_probe_result(&slot, "topology-a", Ok(peer_epochs), now).is_none());
        assert!(slot.read().expect("proof slot should not poison").proof.is_some());
    }

@@ -16,7 +16,7 @@ use super::meta::{
    clone_arc_by_index, ensure_valid_rebalance_pool_index, invalid_rebalance_pool_index_error,
    rebalance_metadata_not_initialized_error, should_ignore_rebalance_data_usage_cache,
 };
-use super::migration::{RebalanceMigrationBackend, migrate_entry_version};
+use super::migration::migrate_entry_version;
 use super::worker::{
    RebalanceEntryCleanupResult, RebalanceEntryTask, load_rebalance_bucket_configs, rebalance_max_attempts,
    resolve_rebalance_bucket_error, resolve_rebalance_entry_cleanup_delete_result, resolve_rebalance_file_info_versions_result,
@@ -144,11 +144,6 @@ impl ECStore {
            return Ok(RebalanceEntryOutcome::Completed);
        }

-        let bucket_incarnation_fence = match bucket_configs.bucket_incarnation_id {
-            Some(expected) => Some(self.acquire_bucket_incarnation_fence(&bucket, expected).await?),
-            None => None,
-        };
-
        let mut fivs =
            resolve_rebalance_file_info_versions_result(entry.file_info_versions(&bucket), bucket.as_str(), entry.name.as_str())?;

@@ -208,14 +203,9 @@ impl ECStore {
            }

            let version_id = version.version_id.map(|v| v.to_string());
-            let expected_bucket_incarnation_id = bucket_configs.bucket_incarnation_id;
            let mut transfer = |src_pool_idx: usize, bucket: String, rd: GetObjectReader| {
                let store = self.clone();
-                async move {
-                    store
-                        .rebalance_object(src_pool_idx, bucket, rd, expected_bucket_incarnation_id)
-                        .await
-                }
+                async move { store.rebalance_object(src_pool_idx, bucket, rd).await }
            };
            // Route delete-marker migration through the store layer so it lands on the
            // cross-pool target (excluding the source pool), not back onto the source set.
@@ -224,12 +214,11 @@ impl ECStore {
                async move { store.delete_object(&bucket, &object, opts).await }
            };
            let result = migrate_entry_version(
-                &RebalanceMigrationBackend::new(set.as_ref(), self.as_ref()),
+                set.as_ref(),
                bucket.clone(),
                pool_index,
                version,
                version_id.clone(),
-                expected_bucket_incarnation_id,
                rebalance_max_attempts(),
                should_ignore_rebalance_data_usage_cache(bucket.as_str()),
                &mut transfer,
@@ -314,9 +303,6 @@ impl ECStore {
        }

        if should_cleanup_rebalance_source_entry(rebalanced, fivs.versions.len(), expired) {
-            if bucket_incarnation_fence.as_ref().is_some_and(|guard| guard.is_lock_lost()) {
-                return Err(Error::other("rebalance bucket incarnation fence was lost before source cleanup"));
-            }
            let cleanup_result = self
                .finish_rebalance_entry_after_cleanup(
                    pool_index,
@@ -329,12 +315,6 @@ impl ECStore {
                        entry.name.as_str(),
                        &fivs,
                        &cleanup_preflight_allowed_missing,
-                        data_movement::SourceCleanupBucketFence {
-                            expected_incarnation_id: bucket_configs.bucket_incarnation_id,
-                            lifecycle_guard: bucket_incarnation_fence
-                                .as_ref()
-                                .and_then(|guard| guard.namespace_lock_guard()),
-                        },
                        "rebalance",
                    ),
                )
@@ -409,14 +389,8 @@ impl ECStore {
    }

    #[tracing::instrument(skip(self, rd))]
-    async fn rebalance_object(
-        self: Arc<Self>,
-        pool_idx: usize,
-        bucket: String,
-        rd: GetObjectReader,
-        expected_bucket_incarnation_id: Option<uuid::Uuid>,
-    ) -> Result<()> {
-        data_movement::migrate_object(self, pool_idx, bucket, rd, expected_bucket_incarnation_id, "rebalance_object").await
+    async fn rebalance_object(self: Arc<Self>, pool_idx: usize, bucket: String, rd: GetObjectReader) -> Result<()> {
+        data_movement::migrate_object(self, pool_idx, bucket, rd, "rebalance_object").await
    }

    async fn update_rebalance_last_error(&self, pool_idx: usize, message: String) -> Result<()> {
@@ -864,10 +864,6 @@ pub(super) fn merge_rebalance_meta(remote: &mut RebalanceMeta, local: &Rebalance
    RebalanceMetaMergeOutcome::Merged
 }

-#[allow(
-    dead_code,
-    reason = "stop-transition helper retained beside stop_rebalance_meta_snapshot; no caller yet (backlog#1823)"
-)]
 pub(super) fn mark_started_rebalance_pools_stopped(meta: &mut RebalanceMeta, stop_time: OffsetDateTime) {
    for pool_stat in meta.pool_stats.iter_mut() {
        if pool_stat.info.status == RebalStatus::Started {
@@ -968,7 +964,6 @@ pub(super) fn rollback_rebalance_start_meta_snapshot_for_id(
    })
 }

-#[allow(dead_code, reason = "asserted by this file's tests (backlog#1823)")]
 pub(super) fn stop_rebalance_meta_snapshot(meta: Option<&mut RebalanceMeta>, now: OffsetDateTime) -> Option<RebalanceMeta> {
    let meta = meta?;
    stop_rebalance_state(meta, now);
@@ -5,7 +5,6 @@ use crate::error::{Error, Result, is_err_object_not_found, is_err_version_not_fo
 use crate::object_api::{GetObjectReader, ObjectInfo, ObjectOptions};
 use crate::set_disk::SetDisks;
 use crate::storage_api_contracts::{object::ObjectIO, range::HTTPRangeSpec};
-use crate::store::ECStore;
 use http::HeaderMap;
 use rustfs_filemeta::FileInfo;
 use rustfs_utils::path::encode_dir_object;
@@ -22,23 +21,15 @@ pub(crate) struct MigrationVersionResult {
    pub error: Option<Error>,
 }

-pub(super) fn rebalance_delete_marker_opts(
-    version: &FileInfo,
-    version_id: Option<String>,
-    src_pool_idx: usize,
-    expected_bucket_incarnation_id: Option<uuid::Uuid>,
-) -> ObjectOptions {
-    let version_suspended = version.version_id.is_none() && version_id.is_none();
+pub(super) fn rebalance_delete_marker_opts(version: &FileInfo, version_id: Option<String>, src_pool_idx: usize) -> ObjectOptions {
    ObjectOptions {
-        versioned: !version_suspended,
-        version_suspended,
-        version_id: version_id.or_else(|| version_suspended.then(|| uuid::Uuid::nil().to_string())),
+        versioned: true,
+        version_id,
        mod_time: version.mod_time,
        src_pool_idx,
        data_movement: true,
        delete_marker: true,
        skip_decommissioned: true,
-        expected_bucket_incarnation_id,
        delete_replication: version
            .replication_state_internal
            .as_ref()
@@ -47,12 +38,7 @@ pub(super) fn rebalance_delete_marker_opts(
    }
 }

-fn rebalance_remote_tiered_opts(
-    version: &FileInfo,
-    version_id: Option<String>,
-    src_pool_idx: usize,
-    expected_bucket_incarnation_id: Option<uuid::Uuid>,
-) -> ObjectOptions {
+fn rebalance_remote_tiered_opts(version: &FileInfo, version_id: Option<String>, src_pool_idx: usize) -> ObjectOptions {
    ObjectOptions {
        versioned: version_id.is_some(),
        version_id,
@@ -60,21 +46,6 @@ fn rebalance_remote_tiered_opts(
        user_defined: version.metadata.clone(),
        src_pool_idx,
        data_movement: true,
-        include_part_checksums: true,
-        http_preconditions: Some(crate::data_movement::data_movement_target_precondition()),
-        expected_bucket_incarnation_id,
-        ..Default::default()
-    }
-}
-
-pub(super) fn rebalance_object_migration_read_opts(version_id: Option<String>) -> ObjectOptions {
-    ObjectOptions {
-        version_id,
-        no_lock: true,
-        data_movement: true,
-        raw_data_movement_read: true,
-        skip_decommissioned: true,
-        skip_rebalancing: true,
        ..Default::default()
    }
 }
@@ -99,19 +70,8 @@ pub(crate) trait MigrationBackend: Send + Sync {
    ) -> Result<()>;
 }

-pub(crate) struct RebalanceMigrationBackend<'a> {
-    source: &'a SetDisks,
-    store: &'a ECStore,
-}
-
-impl<'a> RebalanceMigrationBackend<'a> {
-    pub(crate) fn new(source: &'a SetDisks, store: &'a ECStore) -> Self {
-        Self { source, store }
-    }
-}
-
 #[async_trait::async_trait]
-impl MigrationBackend for RebalanceMigrationBackend<'_> {
+impl MigrationBackend for SetDisks {
    async fn get_object_reader_for_migration(
        &self,
        bucket: &str,
@@ -120,7 +80,7 @@ impl MigrationBackend for RebalanceMigrationBackend<'_> {
        h: HeaderMap,
        opts: &ObjectOptions,
    ) -> Result<GetObjectReader> {
-        self.source.get_object_reader(bucket, object, range, h, opts).await
+        self.get_object_reader(bucket, object, range, h, opts).await
    }

    async fn move_remote_version_for_migration(
@@ -130,7 +90,7 @@ impl MigrationBackend for RebalanceMigrationBackend<'_> {
        fi: &FileInfo,
        opts: &ObjectOptions,
    ) -> Result<()> {
-        self.store.decommission_tiered_object(bucket, object, fi, opts).await
+        self.decommission_tiered_object(bucket, object, fi, opts).await
    }
 }

@@ -141,7 +101,6 @@ pub(crate) async fn migrate_entry_version<Backend, F, Fut, D, DFut>(
    pool_index: usize,
    version: &FileInfo,
    version_id: Option<String>,
-    expected_bucket_incarnation_id: Option<uuid::Uuid>,
    max_attempts: usize,
    ignore_data_usage_cache: bool,
    transfer: F,
@@ -154,13 +113,12 @@ where
    D: FnMut(String, String, ObjectOptions) -> DFut + Send,
    DFut: Future<Output = Result<ObjectInfo>> + Send,
 {
-    migrate_entry_version_with_retry_wait_and_incarnation(
+    migrate_entry_version_with_retry_wait(
        set,
        bucket,
        pool_index,
        version,
        version_id,
-        expected_bucket_incarnation_id,
        max_attempts,
        ignore_data_usage_cache,
        transfer,
@@ -171,7 +129,6 @@ where
 }

 #[allow(clippy::too_many_arguments)]
-#[allow(dead_code, reason = "asserted by this file's tests (backlog#1823)")]
 pub(super) async fn migrate_entry_version_with_retry_wait<Backend, F, Fut, D, DFut, W, WFut>(
    set: &Backend,
    bucket: String,
@@ -180,45 +137,6 @@ pub(super) async fn migrate_entry_version_with_retry_wait<Backend, F, Fut, D, DF
    version_id: Option<String>,
    max_attempts: usize,
    ignore_data_usage_cache: bool,
-    transfer: F,
-    delete_marker: D,
-    wait_retry: W,
-) -> MigrationVersionResult
-where
-    Backend: MigrationBackend + ?Sized,
-    F: FnMut(usize, String, GetObjectReader) -> Fut + Send,
-    Fut: Future<Output = Result<()>> + Send,
-    D: FnMut(String, String, ObjectOptions) -> DFut + Send,
-    DFut: Future<Output = Result<ObjectInfo>> + Send,
-    W: FnMut(Duration) -> WFut + Send,
-    WFut: Future<Output = ()> + Send,
-{
-    migrate_entry_version_with_retry_wait_and_incarnation(
-        set,
-        bucket,
-        pool_index,
-        version,
-        version_id,
-        None,
-        max_attempts,
-        ignore_data_usage_cache,
-        transfer,
-        delete_marker,
-        wait_retry,
-    )
-    .await
-}
-
-#[allow(clippy::too_many_arguments)]
-async fn migrate_entry_version_with_retry_wait_and_incarnation<Backend, F, Fut, D, DFut, W, WFut>(
-    set: &Backend,
-    bucket: String,
-    pool_index: usize,
-    version: &FileInfo,
-    version_id: Option<String>,
-    expected_bucket_incarnation_id: Option<uuid::Uuid>,
-    max_attempts: usize,
-    ignore_data_usage_cache: bool,
    mut transfer: F,
    mut delete_marker: D,
    mut wait_retry: W,
@@ -251,7 +169,7 @@ where
                &bucket,
                &version.name,
                version,
-                &rebalance_remote_tiered_opts(version, version_id, pool_index, expected_bucket_incarnation_id),
+                &rebalance_remote_tiered_opts(version, version_id, pool_index),
            )
            .await
        {
@@ -294,7 +212,7 @@ where
        if let Err(err) = delete_marker(
            bucket.clone(),
            version.name.clone(),
-            rebalance_delete_marker_opts(version, version_id, pool_index, expected_bucket_incarnation_id),
+            rebalance_delete_marker_opts(version, version_id, pool_index),
        )
        .await
        {
@@ -337,7 +255,11 @@ where
                &encode_dir_object(&version.name),
                None,
                HeaderMap::new(),
-                &rebalance_object_migration_read_opts(version_id.clone()),
+                &ObjectOptions {
+                    version_id: version_id.clone(),
+                    no_lock: true,
+                    ..Default::default()
+                },
            )
            .await
        {
@@ -113,8 +113,6 @@ struct LegacyRebalanceMeta {
 struct MigrationBackendSpy {
    get_object_reader: Mutex<Option<core::result::Result<GetObjectReader, Error>>>,
    move_remote: Mutex<Option<core::result::Result<(), Error>>>,
-    get_opts: Mutex<Vec<ObjectOptions>>,
-    move_remote_opts: Mutex<Vec<ObjectOptions>>,
    get_calls: AtomicUsize,
    move_remote_calls: AtomicUsize,
 }
@@ -127,8 +125,6 @@ impl MigrationBackendSpy {
        Self {
            get_object_reader: Mutex::new(get_object_reader),
            move_remote: Mutex::new(move_remote),
-            get_opts: Mutex::new(Vec::new()),
-            move_remote_opts: Mutex::new(Vec::new()),
            get_calls: AtomicUsize::new(0),
            move_remote_calls: AtomicUsize::new(0),
        }
@@ -142,24 +138,6 @@ impl MigrationBackendSpy {
        self.move_remote_calls.load(Ordering::SeqCst)
    }

-    fn last_get_opts(&self) -> ObjectOptions {
-        self.get_opts
-            .lock()
-            .unwrap()
-            .last()
-            .cloned()
-            .expect("reader opts should be captured")
-    }
-
-    fn last_move_remote_opts(&self) -> ObjectOptions {
-        self.move_remote_opts
-            .lock()
-            .unwrap()
-            .last()
-            .cloned()
-            .expect("remote opts should be captured")
-    }
-
    fn make_reader() -> GetObjectReader {
        GetObjectReader {
            stream: Box::new(Cursor::new(vec![0_u8; 3])),
@@ -178,10 +156,9 @@ impl MigrationBackend for MigrationBackendSpy {
        _object: &str,
        _range: Option<HTTPRangeSpec>,
        _h: http::HeaderMap,
-        opts: &ObjectOptions,
+        _opts: &ObjectOptions,
    ) -> Result<GetObjectReader> {
        self.get_calls.fetch_add(1, Ordering::SeqCst);
-        self.get_opts.lock().unwrap().push(opts.clone());
        if let Some(result) = self.get_object_reader.lock().unwrap().take() {
            return result;
        }
@@ -194,10 +171,9 @@ impl MigrationBackend for MigrationBackendSpy {
        _bucket: &str,
        _object: &str,
        _fi: &FileInfo,
-        opts: &ObjectOptions,
+        _opts: &ObjectOptions,
    ) -> Result<()> {
        self.move_remote_calls.fetch_add(1, Ordering::SeqCst);
-        self.move_remote_opts.lock().unwrap().push(opts.clone());
        if let Some(result) = self.move_remote.lock().unwrap().take() {
            return result;
        }
@@ -241,8 +217,7 @@ fn test_rebalance_delete_marker_opts_preserves_replication_state() {
        ..version_deleted()
    };

-    let incarnation = uuid::Uuid::new_v4();
-    let opts = rebalance_delete_marker_opts(&version, Some("version-id".to_string()), 7, Some(incarnation));
+    let opts = rebalance_delete_marker_opts(&version, Some("version-id".to_string()), 7);
    let replication = opts.delete_replication.expect("replication state should be preserved");

    assert!(opts.versioned);
@@ -252,22 +227,11 @@ fn test_rebalance_delete_marker_opts_preserves_replication_state() {
    assert_eq!(opts.src_pool_idx, 7);
    assert_eq!(opts.version_id.as_deref(), Some("version-id"));
    assert_eq!(opts.mod_time, Some(mod_time));
-    assert_eq!(opts.expected_bucket_incarnation_id, Some(incarnation));
    assert_eq!(replication.replica_status, ReplicationStatusType::Replica);
    assert!(replication.delete_marker);
    assert_eq!(replication.replicate_decision_str, "existing");
 }

-#[test]
-fn test_rebalance_delete_marker_opts_preserves_suspended_null_version() {
-    let version = version_deleted();
-    let opts = rebalance_delete_marker_opts(&version, None, 7, None);
-
-    assert!(!opts.versioned);
-    assert!(opts.version_suspended);
-    assert_eq!(opts.version_id.as_deref(), Some(uuid::Uuid::nil().to_string().as_str()));
-}
-
 #[tokio::test]
 async fn test_migrate_entry_version_remote_version_is_moved_without_transfer() {
    let backend = MigrationBackendSpy::new(None, Some(Ok(())));
@@ -284,14 +248,12 @@ async fn test_migrate_entry_version_remote_version_is_moved_without_transfer() {
        }
    };

-    let incarnation = uuid::Uuid::new_v4();
    let result = migrate_entry_version(
        &backend,
        "bucket".to_string(),
        0,
        &version,
        version.version_id.map(|v| v.to_string()),
-        Some(incarnation),
        3,
        false,
        &mut transfer,
@@ -307,10 +269,6 @@ async fn test_migrate_entry_version_remote_version_is_moved_without_transfer() {
    assert_eq!(transfer_count.load(Ordering::SeqCst), 0);
    assert_eq!(backend.move_remote_calls(), 1);
    assert_eq!(backend.get_calls(), 0);
-    let remote_opts = backend.last_move_remote_opts();
-    assert!(remote_opts.include_part_checksums);
-    assert!(remote_opts.http_preconditions.is_some());
-    assert_eq!(remote_opts.expected_bucket_incarnation_id, Some(incarnation));
 }

 #[tokio::test]
@@ -336,7 +294,6 @@ async fn test_migrate_entry_version_remote_not_found_is_cleanup_ignored() {
        0,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        3,
        false,
        &mut transfer,
@@ -373,7 +330,6 @@ async fn test_migrate_entry_version_remote_overwrite_is_not_ignored() {
        0,
        &version,
        Some("vid-1".to_string()),
-        None,
        3,
        false,
        &mut transfer,
@@ -412,7 +368,6 @@ async fn test_migrate_entry_version_remote_failure_is_reported() {
        0,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        3,
        false,
        &mut transfer,
@@ -455,7 +410,6 @@ async fn test_migrate_entry_version_deleted_version_routes_delete_through_store_
        1,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        3,
        false,
        &mut transfer,
@@ -495,7 +449,6 @@ async fn test_migrate_entry_version_deleted_version_not_found_is_ignored() {
        1,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        3,
        false,
        &mut transfer,
@@ -538,7 +491,6 @@ async fn test_migrate_entry_version_deleted_version_overwrite_is_not_ignored() {
        1,
        &version,
        Some("vid-1".to_string()),
-        None,
        3,
        false,
        &mut transfer,
@@ -568,7 +520,6 @@ async fn test_migrate_entry_version_reader_not_found_is_ignored() {
        1,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        3,
        false,
        &mut transfer,
@@ -696,7 +647,6 @@ async fn test_migrate_entry_version_reader_fails_after_retries() {
        1,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        3,
        false,
        &mut transfer,
@@ -735,7 +685,6 @@ async fn test_migrate_entry_version_zero_max_attempts_still_attempts_once() {
        1,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        0,
        false,
        &mut transfer,
@@ -801,13 +750,6 @@ async fn test_migrate_entry_version_transfer_retries_before_success() {
    assert_eq!(backend.get_calls(), 2);
    assert_eq!(transfer_count.load(Ordering::SeqCst), 2);
    assert_eq!(wait_count.load(Ordering::SeqCst), 1);
-    let read_opts = backend.last_get_opts();
-    assert_eq!(read_opts.version_id.as_deref(), version.version_id.map(|id| id.to_string()).as_deref());
-    assert!(read_opts.no_lock);
-    assert!(read_opts.data_movement);
-    assert!(read_opts.raw_data_movement_read);
-    assert!(read_opts.skip_decommissioned);
-    assert!(read_opts.skip_rebalancing);
 }

 #[tokio::test]
@@ -880,7 +822,6 @@ async fn test_migrate_entry_version_transfer_fails_after_retries() {
        1,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        2,
        false,
        &mut transfer,
@@ -919,7 +860,6 @@ async fn test_migrate_entry_version_transfer_not_found_is_ignored() {
        1,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        3,
        false,
        &mut transfer,
@@ -961,7 +901,6 @@ async fn test_migrate_entry_version_transfer_overwrite_is_not_ignored() {
        1,
        &version,
        Some("vid-1".to_string()),
-        None,
        3,
        false,
        &mut transfer,
@@ -1004,7 +943,6 @@ async fn test_migrate_entry_version_ignores_data_usage_cache_when_enabled() {
        1,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        2,
        true,
        &mut transfer,
@@ -1047,7 +985,6 @@ async fn test_migrate_entry_version_data_usage_cache_moves_when_ignore_disabled(
        1,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        2,
        false,
        &mut transfer,
@@ -2089,7 +2026,6 @@ async fn test_migrate_entry_version_transfer_failure_reports_write_target_stage(
        1,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        1,
        false,
        &mut transfer,
@@ -2114,7 +2050,6 @@ async fn test_migrate_entry_version_reader_failure_reports_read_source_stage() {
        1,
        &version,
        version.version_id.map(|v| v.to_string()),
-        None,
        1,
        false,
        &mut transfer,
@@ -1,4 +1,5 @@
 use serde::{Deserialize, Serialize};
+use std::sync::Arc;
 use time::OffsetDateTime;
 use tokio_util::sync::CancellationToken;

@@ -31,9 +32,10 @@ pub struct RebalanceStats {
    pub cleanup_warnings: RebalanceCleanupWarnings,
 }

+pub type RStats = Vec<Arc<RebalanceStats>>;
+
 #[derive(Debug, Default)]
 pub(super) struct RebalanceBucketConfigs {
-    pub(super) bucket_incarnation_id: Option<uuid::Uuid>,
    pub(super) lifecycle_config: Option<s3s::dto::BucketLifecycleConfiguration>,
    pub(super) object_lock_config: Option<s3s::dto::ObjectLockConfiguration>,
    pub(super) replication_config: Option<(s3s::dto::ReplicationConfiguration, OffsetDateTime)>,
@@ -406,7 +406,6 @@ pub(super) async fn load_rebalance_bucket_configs(api: &ECStore, bucket: &str) -

    let expiry_configs = crate::bucket::lifecycle::get_expiry_configs(api, bucket).await?;
    Ok(RebalanceBucketConfigs {
-        bucket_incarnation_id: Some(api.bucket_incarnation_id_from_disk(bucket).await?),
        lifecycle_config: expiry_configs.lifecycle.map(|config| (*config).clone()),
        object_lock_config: expiry_configs.object_lock.map(|config| (*config).clone()),
        replication_config: resolve_rebalance_optional_bucket_config_result(
@@ -30,5 +30,6 @@ pub mod warm_backend_minio;
 pub mod warm_backend_r2;
 pub mod warm_backend_rustfs;
 pub mod warm_backend_s3;
+pub mod warm_backend_s3sdk;
 pub mod warm_backend_tencent;
 pub mod warm_backend_wasabi;
@@ -488,7 +488,6 @@ impl TierCandidateMutation {
        targets
    }

-    #[allow(dead_code, reason = "asserted by this file's tests (backlog#1823)")]
    fn affected_targets(
        &self,
        manager: &TierConfigMgr,
@@ -803,7 +802,6 @@ fn tier_persisted_reference_blocks_any_target(
        .any(|target| tier_persisted_reference_blocks_target(tier_name, backend_identity, target))
 }

-#[allow(dead_code, reason = "asserted by this file's tests (backlog#1823)")]
 fn tier_object_blocks_target_rebind(object: &ObjectInfo, target: &TierMutationIntentTarget) -> io::Result<bool> {
    tier_object_blocks_any_target_rebind(object, std::slice::from_ref(target))
 }
@@ -2728,6 +2726,14 @@ impl TierConfigMgr {
        Self::publish_candidate_owned(handle, candidate, driver_tier.map(str::to_string), update).await
    }

+    fn begin_publish_transition(
+        handle: &Arc<RwLock<Self>>,
+        manager: &mut Self,
+        candidate: &Self,
+    ) -> std::result::Result<TierPublishTransition, AdminError> {
+        Self::begin_publish_transition_with_allowed_mutation_blocks(handle, manager, candidate, None)
+    }
+
    fn begin_publish_transition_with_allowed_mutation_blocks(
        handle: &Arc<RwLock<Self>>,
        manager: &mut Self,
@@ -2813,6 +2819,14 @@ impl TierConfigMgr {
        })
    }

+    async fn publish_candidate_inner(
+        handle: &Arc<RwLock<Self>>,
+        candidate: Self,
+        driver_tier: Option<&str>,
+    ) -> std::result::Result<(), AdminError> {
+        Self::publish_candidate_inner_with_allowed_mutation_blocks(handle, candidate, driver_tier, None).await
+    }
+
    async fn publish_candidate_inner_with_allowed_mutation_blocks(
        handle: &Arc<RwLock<Self>>,
        candidate: Self,
@@ -2925,7 +2939,6 @@ impl TierConfigMgr {
        admin_err
    }

-    #[allow(dead_code, reason = "reached only through #[cfg(test)] helpers in this file (backlog#1823)")]
    async fn publish_candidate_owned(
        handle: &Arc<RwLock<Self>>,
        candidate: Self,
@@ -3528,7 +3541,6 @@ impl TierConfigMgr {
        Self::update_candidate_with_config_lock(handle, api, TierCandidateMutation::Remove(tier_name.to_string(), force)).await
    }

-    #[allow(dead_code, reason = "reached only through #[cfg(test)] helpers in this file (backlog#1823)")]
    async fn remove_and_save_with<S>(
        handle: &Arc<RwLock<Self>>,
        api: Arc<S>,
@@ -3562,7 +3574,6 @@ impl TierConfigMgr {
        Self::update_candidate_with_config_lock(handle, api, TierCandidateMutation::Clear(force)).await
    }

-    #[allow(dead_code, reason = "reached only through #[cfg(test)] helpers in this file (backlog#1823)")]
    async fn clear_and_save_with<S>(
        handle: &Arc<RwLock<Self>>,
        api: Arc<S>,
@@ -3601,10 +3612,6 @@ impl TierConfigMgr {
    }

    #[cfg(test)]
-    #[allow(
-        dead_code,
-        reason = "lease accounting asserted by a bucket_lifecycle_ops test behind `--features test-util` (backlog#1823)"
-    )]
    pub(crate) async fn active_operation_lease_count(handle: &Arc<RwLock<Self>>, tier_name: &str) -> usize {
        let manager = handle.read().await;
        let Some(runtime) = registered_tier_driver_runtime(&manager) else {
@@ -3710,6 +3717,10 @@ impl TierConfigMgr {
        Ok(())
    }

+    fn retire_driver(&mut self, tier_name: &str) {
+        self.revoke_driver(tier_name);
+    }
+
    fn revoke_all_drivers(&mut self) {
        if let Some(runtime) = registered_tier_driver_runtime(self) {
            let mut runtime = lock_unpoisoned(&runtime);
@@ -3873,7 +3884,6 @@ impl TierConfigMgr {
        self.save_config(api, &config_file, data).await
    }

-    #[allow(dead_code, reason = "reached only through #[cfg(test)] helpers in this file (backlog#1823)")]
    async fn save_tiering_config_if_current<S>(
        &self,
        api: Arc<S>,
@@ -305,10 +305,6 @@ impl TierMutationIntent {
    }
 }

-#[allow(
-    dead_code,
-    reason = "intent-record persistence asserted by store::init tests (backlog#1823)"
-)]
 pub(crate) fn tier_mutation_intent_record_object_name(mutation_id: Uuid) -> Result<String> {
    tier_mutation_intent_record_object_name_with_prefix(TIER_MUTATION_INTENT_RECORD_PREFIX, mutation_id)
 }
@@ -321,10 +317,6 @@ fn tier_mutation_intent_record_object_name_with_prefix(prefix: &str, mutation_id
    Ok(format!("{}/{}/{}/{}.json", prefix, &mutation_key[..2], &mutation_key[2..4], mutation_key))
 }

-#[allow(
-    dead_code,
-    reason = "intent-record persistence asserted by store::init tests (backlog#1823)"
-)]
 pub(crate) fn tier_mutation_intent_id_from_record_object_name(object: &str) -> Result<Uuid> {
    tier_mutation_intent_id_from_record_object_name_with_prefix(TIER_MUTATION_INTENT_RECORD_PREFIX, object)
 }
@@ -363,10 +355,6 @@ fn tier_mutation_intent_id_from_record_object_name_with_prefix(prefix: &str, obj
    Uuid::parse_str(mutation_key).map_err(|_| TierMutationIntentError::Corrupt("intent record path has invalid uuid"))
 }

-#[allow(
-    dead_code,
-    reason = "intent-record persistence asserted by store::init tests (backlog#1823)"
-)]
 pub(crate) async fn save_tier_mutation_intent_record<S>(api: Arc<S>, intent: &TierMutationIntent) -> EcstoreResult<()>
 where
    S: EcstoreObjectIO,
@@ -458,10 +446,6 @@ where
    Ok((intent, etag))
 }

-#[allow(
-    dead_code,
-    reason = "intent-record persistence asserted by store::init tests (backlog#1823)"
-)]
 pub(crate) async fn save_tier_mutation_intent_record_if_current<S>(
    api: Arc<S>,
    intent: &TierMutationIntent,
@@ -41,7 +41,10 @@ use crate::services::tier::{
 };
 use tracing::warn;

+const MAX_MULTIPART_PUT_OBJECT_SIZE: i64 = 1024 * 1024 * 1024 * 1024 * 5;
+const MAX_PARTS_COUNT: i64 = 10000;
 const _MAX_PART_SIZE: i64 = 1024 * 1024 * 1024 * 5;
+const MIN_PART_SIZE: i64 = 1024 * 1024 * 128;

 fn parse_generation(remote_version: &str) -> Result<Option<i64>, Error> {
    if remote_version.is_empty() {
@@ -61,6 +64,7 @@ pub struct WarmBackendGCS {
    pub control: Arc<StorageControl>,
    pub bucket: String,
    pub prefix: String,
+    pub storage_class: String,
 }

 impl WarmBackendGCS {
@@ -100,6 +104,7 @@ impl WarmBackendGCS {
            control,
            bucket: conf.bucket.clone(),
            prefix: conf.prefix.strip_suffix("/").unwrap_or(&conf.prefix).to_owned(),
+            storage_class: "".to_string(),
        })
    }

@@ -33,6 +33,8 @@ use crate::client::{
    transition_api::{BucketLookupType, Options, TransitionClient, TransitionCore},
    transition_api::{ReadCloser, ReaderImpl},
 };
+use crate::error::ErrorResponse;
+use crate::error::error_resp_to_object_err;
 use crate::services::tier::{
    tier_config::TierS3,
    warm_backend::{
@@ -0,0 +1,200 @@
+// Copyright 2024 RustFS Team
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#![allow(unused_imports)]
+#![allow(unused_variables)]
+#![allow(unused_mut)]
+#![allow(unused_assignments)]
+#![allow(unused_must_use)]
+#![allow(clippy::all)]
+
+use std::collections::HashMap;
+use std::sync::Arc;
+use url::Url;
+
+use aws_config::meta::region::RegionProviderChain;
+use aws_sdk_s3::Client;
+use aws_sdk_s3::config::{Credentials, Region};
+use aws_sdk_s3::primitives::ByteStream;
+
+use crate::client::{
+    api_get_options::GetObjectOptions,
+    api_put_object::PutObjectOptions,
+    api_remove::RemoveObjectOptions,
+    transition_api::{ReadCloser, ReaderImpl},
+};
+use crate::error::ErrorResponse;
+use crate::error::error_resp_to_object_err;
+use crate::services::tier::{
+    tier_config::TierS3,
+    warm_backend::{WarmBackend, WarmBackendGetOpts},
+};
+
+pub struct WarmBackendS3 {
+    pub client: Arc<Client>,
+    pub bucket: String,
+    pub prefix: String,
+    pub storage_class: String,
+}
+
+impl WarmBackendS3 {
+    pub async fn new(conf: &TierS3, tier: &str) -> Result<Self, std::io::Error> {
+        let u = match Url::parse(&conf.endpoint) {
+            Ok(u) => u,
+            Err(err) => {
+                return Err(std::io::Error::other(err.to_string()));
+            }
+        };
+
+        if conf.aws_role_web_identity_token_file == "" && conf.aws_role_arn != ""
+            || conf.aws_role_web_identity_token_file != "" && conf.aws_role_arn == ""
+        {
+            return Err(std::io::Error::other("both the token file and the role ARN are required"));
+        } else if conf.access_key == "" && conf.secret_key != "" || conf.access_key != "" && conf.secret_key == "" {
+            return Err(std::io::Error::other("both the access and secret keys are required"));
+        } else if conf.aws_role
+            && (conf.aws_role_web_identity_token_file != ""
+                || conf.aws_role_arn != ""
+                || conf.access_key != ""
+                || conf.secret_key != "")
+        {
+            return Err(std::io::Error::other(
+                "AWS Role cannot be activated with static credentials or the web identity token file",
+            ));
+        } else if conf.bucket == "" {
+            return Err(std::io::Error::other("no bucket name was provided"));
+        }
+
+        let creds;
+        if conf.access_key != "" && conf.secret_key != "" {
+            creds = Credentials::new(
+                conf.access_key.clone(), // access_key_id
+                conf.secret_key.clone(), // secret_access_key
+                None,                    // session_token (optional)
+                None,
+                "Static",
+            );
+        } else {
+            return Err(std::io::Error::other("insufficient parameters for S3 backend authentication"));
+        }
+        let region_provider = RegionProviderChain::default_provider().or_else(Region::new(conf.region.clone()));
+        #[allow(deprecated)]
+        let config = aws_config::from_env()
+            .endpoint_url(conf.endpoint.clone())
+            .region(region_provider)
+            .credentials_provider(creds)
+            .load()
+            .await;
+        let client = Client::new(&config);
+        let client = Arc::new(client);
+        Ok(Self {
+            client,
+            bucket: conf.bucket.clone(),
+            prefix: conf.prefix.clone().trim_matches('/').to_string(),
+            storage_class: conf.storage_class.clone(),
+        })
+    }
+
+    pub fn get_dest(&self, object: &str) -> String {
+        let mut dest_obj = object.to_string();
+        if self.prefix != "" {
+            dest_obj = format!("{}/{}", &self.prefix, object);
+        }
+        return dest_obj;
+    }
+}
+
+#[async_trait::async_trait]
+impl WarmBackend for WarmBackendS3 {
+    async fn put_with_meta(
+        &self,
+        object: &str,
+        r: ReaderImpl,
+        length: i64,
+        meta: HashMap<String, String>,
+    ) -> Result<String, std::io::Error> {
+        let client = self.client.clone();
+        let Ok(res) = client
+            .put_object()
+            .bucket(&self.bucket)
+            .key(&self.get_dest(object))
+            .body(match r {
+                ReaderImpl::Body(content_body) => ByteStream::from(content_body.to_vec()),
+                ReaderImpl::ObjectBody(mut content_body) => ByteStream::from(content_body.read_all().await?),
+            })
+            .send()
+            .await
+        else {
+            return Err(std::io::Error::other("put_object error"));
+        };
+
+        Ok(res.version_id().unwrap_or("").to_string())
+    }
+
+    async fn put(&self, object: &str, r: ReaderImpl, length: i64) -> Result<String, std::io::Error> {
+        self.put_with_meta(object, r, length, HashMap::new()).await
+    }
+
+    async fn get(&self, object: &str, rv: &str, opts: WarmBackendGetOpts) -> Result<ReadCloser, std::io::Error> {
+        let client = self.client.clone();
+        let mut req = client.get_object().bucket(&self.bucket).key(&self.get_dest(object));
+
+        if !rv.is_empty() {
+            req = req.version_id(rv);
+        }
+
+        if opts.start_offset >= 0 && opts.length > 0 {
+            let end = opts
+                .start_offset
+                .checked_add(opts.length)
+                .and_then(|v| v.checked_sub(1))
+                .ok_or_else(|| std::io::Error::other("invalid range: overflow"))?;
+            req = req.range(format!("bytes={}-{}", opts.start_offset, end));
+        }
+
+        let res = req.send().await.map_err(|e| std::io::Error::other(e.to_string()))?;
+
+        Ok(ReadCloser::new(std::io::Cursor::new(
+            res.body.collect().await.map(|data| data.into_bytes().to_vec())?,
+        )))
+    }
+
+    async fn remove(&self, object: &str, rv: &str) -> Result<(), std::io::Error> {
+        let client = self.client.clone();
+        let mut req = client.delete_object().bucket(&self.bucket).key(&self.get_dest(object));
+
+        if !rv.is_empty() {
+            req = req.version_id(rv);
+        }
+
+        req.send().await.map_err(|e| std::io::Error::other(e.to_string()))?;
+
+        Ok(())
+    }
+
+    async fn in_use(&self) -> Result<bool, std::io::Error> {
+        let client = self.client.clone();
+        let Ok(res) = client
+            .list_objects_v2()
+            .bucket(&self.bucket)
+            //.max_keys(10)
+            //.into_paginator()
+            .send()
+            .await
+        else {
+            return Err(std::io::Error::other("list_objects_v2 error"));
+        };
+
+        Ok(res.common_prefixes.unwrap_or_default().len() > 0 || res.contents.unwrap_or_default().len() > 0)
+    }
+}
@@ -85,15 +85,6 @@ impl SetDisks {
        format!("{}/{}", Self::get_multipart_sha_dir(bucket, object), upload_uuid)
    }

-    pub(super) fn get_multipart_upload_dir(bucket: &str, object: &str, upload_id: &str, data_movement: bool) -> String {
-        let upload_dir = Self::get_upload_id_dir(bucket, object, upload_id);
-        if data_movement {
-            format!("{DATA_MOVEMENT_MULTIPART_PREFIX}/{upload_dir}")
-        } else {
-            upload_dir
-        }
-    }
-
    pub(super) fn get_multipart_sha_dir(bucket: &str, object: &str) -> String {
        let path = format!("{bucket}/{object}");
        let mut hasher = Sha256::new();
@@ -475,28 +466,6 @@ impl SetDisks {
        Self::find_file_info_in_quorum(metas, &mod_time, &etag, quorum)
    }

-    pub(crate) fn hydrate_selected_fileinfo_part_checksums(fi: &mut FileInfo) -> disk::error::Result<()> {
-        fi.hydrate_data_movement_part_checksums().map_err(DiskError::from)?;
-        for part in &fi.parts {
-            let Some(checksums) = part.checksums.as_ref() else {
-                continue;
-            };
-            let mut algorithms = HashSet::with_capacity(checksums.len());
-            for (name, value) in checksums {
-                let Some(checksum) = rustfs_rio::Checksum::new_from_string(name, value) else {
-                    return Err(DiskError::FileCorrupt);
-                };
-                if checksum.checksum_type.is(rustfs_rio::ChecksumType::MULTIPART) {
-                    return Err(DiskError::FileCorrupt);
-                }
-                if !algorithms.insert(checksum.checksum_type.base().0) {
-                    return Err(DiskError::FileCorrupt);
-                }
-            }
-        }
-        Ok(())
-    }
-
    fn update_hash_bytes(hasher: &mut Sha256, value: &[u8]) {
        hasher.update(value.len().to_le_bytes());
        hasher.update(value);
@@ -1110,25 +1079,6 @@ impl SetDisks {
        shuffled_disks
    }

-    pub(super) fn shuffle_disks_owned(mut disks: Vec<Option<DiskStore>>, distribution: &[usize]) -> Vec<Option<DiskStore>> {
-        if distribution.is_empty() {
-            return disks;
-        }
-
-        let mut shuffled_disks = vec![None; disks.len()];
-        for (index, disk) in disks.iter_mut().enumerate() {
-            let Some(slot) = distribution
-                .get(index)
-                .and_then(|block_index| block_index.checked_sub(1))
-                .filter(|slot| *slot < shuffled_disks.len())
-            else {
-                continue;
-            };
-            shuffled_disks[slot] = disk.take();
-        }
-        shuffled_disks
-    }
-
    pub(super) fn shuffle_check_parts(parts_errs: &[usize], distribution: &[usize]) -> Vec<usize> {
        if distribution.is_empty() {
            return parts_errs.to_vec();
@@ -1440,23 +1390,6 @@ mod tests {
        assert_eq!(owned_slots, expected_slots, "fallback disk slots must match the borrowing variant");
    }

-    #[tokio::test]
-    async fn owned_shuffle_preserves_fresh_put_metadata() {
-        let tempdir = tempfile::tempdir().expect("tempdir should be created");
-        let fi = FileInfo::new("bucket/object", 2, 1);
-        let parts = vec![fi.clone(); fi.erasure.distribution.len()];
-        let disks = shuffle_test_disks(&tempdir, parts.len()).await;
-
-        let (owned_disks, owned_parts) = SetDisks::shuffle_disks_and_parts_metadata_by_index_owned(disks, parts, &fi);
-
-        assert!(owned_disks.iter().all(Option::is_some), "fresh PUT must retain every online disk");
-        assert_eq!(
-            owned_parts,
-            vec![fi; owned_disks.len()],
-            "fresh PUT metadata with pending shard indexes must survive init fallback"
-        );
-    }
-
    // backlog#949: corrupt/adversarial distribution values (0 or > N) must not
    // trigger a `usize` underflow / out-of-bounds panic in the shuffle helpers.
    #[test]
@@ -1486,22 +1419,6 @@ mod tests {
        assert_eq!(result.len(), disks.len(), "output length must be preserved");
    }

-    #[tokio::test]
-    async fn owned_disk_shuffle_matches_borrowing_variant() {
-        let tempdir = tempfile::tempdir().expect("tempdir should be created");
-        let mut disks = shuffle_test_disks(&tempdir, 4).await;
-        disks[1] = None;
-        disks[3] = None;
-        let distribution = [3, 1, 4, 2];
-
-        let expected = SetDisks::shuffle_disks(&disks, &distribution);
-        let actual = SetDisks::shuffle_disks_owned(disks, &distribution);
-
-        let expected_slots = expected.iter().map(Option::is_some).collect::<Vec<_>>();
-        let actual_slots = actual.iter().map(Option::is_some).collect::<Vec<_>>();
-        assert_eq!(actual_slots, expected_slots, "owned shuffle must preserve disk placement");
-    }
-
    #[tokio::test]
    async fn shuffle_disks_and_parts_metadata_survives_corrupt_distribution() {
        let tempdir = tempfile::tempdir().expect("tempdir should be created");
@@ -13,7 +13,6 @@
 // limitations under the License.

 use super::super::*;
-use crate::disk::disk_store::DiskStoreRenameDataExt;
 use crate::io_support::bitrot::object_mmap_read_enabled;
 use crate::storage_api_contracts::namespace::NamespaceLocking as _;
 use tracing::trace;
@@ -543,8 +542,7 @@ impl SetDisks {

                let filter_by_etag = quorum_etag.is_some();
                match Self::pick_valid_fileinfo(&parts_metadata, quorum_mod_time, quorum_etag.clone(), read_quorum as usize) {
-                    Ok(mut latest_meta) => {
-                        Self::hydrate_selected_fileinfo_part_checksums(&mut latest_meta)?;
+                    Ok(latest_meta) => {
                        trace!(
                            event = EVENT_SET_DISK_HEAL,
                            component = LOG_COMPONENT_ECSTORE,
@@ -1165,10 +1163,10 @@ impl SetDisks {
                                let rename_result = if should_fail_heal_rename(bucket, object, index) {
                                    Err(DiskError::Unexpected)
                                } else {
-                                    disk.rename_data_borrowed(
+                                    disk.rename_data(
                                        RUSTFS_META_TMP_BUCKET,
                                        &tmp_id,
-                                        &parts_metadata[index],
+                                        parts_metadata[index].clone(),
                                        bucket,
                                        object,
                                    )
@@ -1426,33 +1424,6 @@ impl SetDisks {
    /// post-heal tail — reclaim identically. Never fails the heal: delete errors
    /// are logged and swallowed. Callers must gate this on `!opts.dry_run`.
    async fn reclaim_orphan_data_dirs_best_effort(&self, bucket: &str, object: &str) {
-        match self.reconcile_old_data_cleanup_receipts(bucket, object).await {
-            Ok(removed) if removed > 0 => {
-                debug!(
-                    event = EVENT_SET_DISK_HEAL,
-                    component = LOG_COMPONENT_ECSTORE,
-                    subsystem = LOG_SUBSYSTEM_SET_DISK,
-                    bucket,
-                    object,
-                    removed,
-                    state = "old_data_cleanup_receipt_reconciled",
-                    "Set disk old-data cleanup receipts reconciled"
-                );
-            }
-            Ok(_) => {}
-            Err(e) => {
-                warn!(
-                    event = EVENT_SET_DISK_HEAL,
-                    component = LOG_COMPONENT_ECSTORE,
-                    subsystem = LOG_SUBSYSTEM_SET_DISK,
-                    bucket,
-                    object,
-                    error = %e,
-                    state = "old_data_cleanup_receipt_reconcile_failed",
-                    "Set disk old-data cleanup receipt reconcile failed"
-                );
-            }
-        }
        match self.reclaim_orphan_data_dirs(bucket, object).await {
            Ok(removed) if removed > 0 => {
                debug!(
@@ -3199,11 +3170,10 @@ mod heal_result_report_tests {
            .await
            .expect("object should be written");

-        let snapshot = set
+        let (fi, _, _) = set
            .get_object_fileinfo(bucket, object, &opts, true, false)
            .await
            .expect("object metadata should resolve");
-        let fi = snapshot.fi();
        assert_eq!(fi.erasure.parity_blocks, 0);
        let data_dir = fi.data_dir.expect("non-inline object should have a data directory");
        let part_path = dir.path().join(bucket).join(object).join(data_dir.to_string()).join("part.1");
@@ -36,21 +36,10 @@ impl crate::storage_api_contracts::namespace::NamespaceLocking for SetDisks {
        // test's transient DistErasure window) would push this set's namespace
        // locking onto its own — possibly empty — dist locker list.
        let set_lock = if self.ctx.is_dist_erasure().await {
-            let lockers = if self.lockers.len() == self.shared_lockers.len()
-                && self
-                    .lockers
-                    .iter()
-                    .zip(self.shared_lockers.iter())
-                    .all(|(current, shared)| Arc::ptr_eq(current, shared))
-            {
-                self.shared_lockers.clone()
-            } else {
-                Arc::from(self.lockers.clone())
-            };
-            // Calculate quorum from the exact client domain used by this lock.
-            let lockers_count = lockers.len();
+            // Calculate quorum based on lockers count (majority)
+            let lockers_count = self.lockers.len();
            let write_quorum = if lockers_count > 1 { (lockers_count / 2) + 1 } else { 1 };
-            NamespaceLock::with_clients_and_quorum_shared(self.set_lock_namespace.clone(), lockers, write_quorum)
+            NamespaceLock::with_clients_and_quorum_shared(self.set_lock_namespace.clone(), self.lockers.clone(), write_quorum)
        } else {
            NamespaceLock::with_local_manager_shared(self.set_lock_namespace.clone(), self.local_lock_manager.clone())
        };
@@ -19,7 +19,7 @@ use crate::diagnostics::get::{
    GET_METADATA_CACHE_REASON_DATA_MOVEMENT, GET_METADATA_CACHE_REASON_DELETE_MARKER, GET_METADATA_CACHE_REASON_DIST_ERASURE,
    GET_METADATA_CACHE_REASON_INCL_FREE_VERSIONS, GET_METADATA_CACHE_REASON_INSUFFICIENT_CACHED_QUORUM,
    GET_METADATA_CACHE_REASON_META_BUCKET, GET_METADATA_CACHE_REASON_NO_LOCK, GET_METADATA_CACHE_REASON_NOT_FOUND_OR_EXPIRED,
-    GET_METADATA_CACHE_REASON_NOT_READ_DATA, GET_METADATA_CACHE_REASON_PART_CHECKSUMS, GET_METADATA_CACHE_REASON_PART_NUMBER,
+    GET_METADATA_CACHE_REASON_NOT_READ_DATA, GET_METADATA_CACHE_REASON_PART_NUMBER,
    GET_METADATA_CACHE_REASON_RAW_DATA_MOVEMENT_READ, GET_METADATA_CACHE_REASON_STALE_PUBLICATION,
    GET_METADATA_CACHE_REASON_USABLE, GET_METADATA_CACHE_REASON_VERSION_ID, GET_METADATA_CACHE_REASON_VERSION_SUSPENDED,
    GET_METADATA_CACHE_REASON_VERSIONED, GET_METADATA_EARLY_STOP_REASON_CONFLICTING_METADATA,
@@ -180,9 +180,9 @@ impl SetDisks {
        let key = GetObjectMetadataCacheKey::new(bucket, object, generation);
        let entry = Arc::new(GetObjectMetadataCacheEntry {
            created_at: Instant::now(),
-            fi: fi.clone(),
-            parts_metadata: parts_metadata.to_vec(),
-            online_disks: online_disks.to_vec(),
+            fi: Arc::new(fi.clone()),
+            parts_metadata: Arc::new(parts_metadata.to_vec()),
+            online_disks: Arc::new(online_disks.to_vec()),
            read_quorum,
        });
        self.insert_get_object_metadata_cache_entry_after_insert(key, generation, entry, || {})
@@ -300,7 +300,11 @@ impl SetDisks {
                        GET_STAGE_METADATA_CACHE_LOOKUP,
                        metadata_cache_lookup_start,
                    );
-                    return Ok(GetObjectFileInfo::shared(cached));
+                    return Ok((
+                        GetObjectMetadata::Shared(Arc::clone(&cached.fi)),
+                        GetObjectMetadata::Shared(Arc::clone(&cached.parts_metadata)),
+                        GetObjectMetadata::Shared(Arc::clone(&cached.online_disks)),
+                    ));
                }
                MetadataCacheLookup::Miss => {
                    rustfs_io_metrics::record_get_object_metadata_cache_decision(
@@ -336,7 +340,7 @@ impl SetDisks {
        // read_all_fileinfo_observed (see read_all_fileinfo_early_stop in
        // core/io_primitives.rs); unsafe requests and callers that opt out
        // (allow_early_stop=false) fall back to full-wait.
-        let (mut parts_metadata, errs, metadata_fanout_diagnostics) = Self::read_all_fileinfo_observed(
+        let (parts_metadata, errs, metadata_fanout_diagnostics) = Self::read_all_fileinfo_observed(
            &disks,
            "",
            bucket,
@@ -390,17 +394,8 @@ impl SetDisks {
            return Err(to_object_err(err.into(), vec![bucket, object]));
        }

-        let (op_online_disks, mut fi, fileinfo_selection_quorum) =
+        let (op_online_disks, fi, fileinfo_selection_quorum) =
            Self::select_valid_fileinfo(&disks, &parts_metadata, &errs, vid.as_str(), read_quorum, write_quorum)?;
-        let include_part_checksums =
-            opts.include_part_checksums || opts.part_number.is_some() || opts.data_movement || opts.raw_data_movement_read;
-        if include_part_checksums {
-            Self::hydrate_selected_fileinfo_part_checksums(&mut fi)?;
-        } else {
-            for metadata in std::iter::once(&mut fi).chain(parts_metadata.iter_mut()) {
-                rustfs_utils::http::remove_str(&mut metadata.metadata, rustfs_utils::http::SUFFIX_PART_CHECKSUMS);
-            }
-        }
        metadata_fanout_diagnostics.record_quorum_candidate_latency(metadata_metrics_path, fileinfo_selection_quorum);
        if errs.iter().any(|err| err.is_some()) {
            let version_id = resolved_read_repair_version_id(&fi, opts.version_id.as_deref());
@@ -432,7 +427,11 @@ impl SetDisks {

        // let online_disks: Vec<Option<DiskStore>> = op_online_disks.iter().filter(|v| v.is_some()).cloned().collect();

-        Ok(GetObjectFileInfo::owned(fi, parts_metadata, op_online_disks))
+        Ok((
+            GetObjectMetadata::Owned(fi),
+            GetObjectMetadata::Owned(parts_metadata),
+            GetObjectMetadata::Owned(op_online_disks),
+        ))
    }

    #[hotpath::measure(impl_type = "SetDisks")]
@@ -442,15 +441,14 @@ impl SetDisks {
        object: &str,
        opts: &ObjectOptions,
    ) -> (ObjectInfo, usize, Option<StorageError>) {
-        let snapshot = match self.get_object_fileinfo(bucket, object, opts, false, false).await {
-            Ok(snapshot) => snapshot,
+        let fi = match self.get_object_fileinfo(bucket, object, opts, false, false).await {
+            Ok((fi, _, _)) => fi,
            Err(e) => return (ObjectInfo::default(), 0, Some(e)),
        };
-        let fi = snapshot.fi();

        let write_quorum = fi.write_quorum(self.default_write_quorum());

-        let oi = ObjectInfo::from_file_info(fi, bucket, object, opts.versioned || opts.version_suspended);
+        let oi = ObjectInfo::from_file_info(&fi, bucket, object, opts.versioned || opts.version_suspended);

        if !fi.version_purge_status().is_empty() && opts.version_id.is_some() {
            return (
@@ -482,7 +480,6 @@ impl SetDisks {
    pub(super) async fn try_get_object_direct_data_shards_with_fileinfo(
        bucket: &str,
        object: &str,
-        erasure_cache: Arc<ErasureCache>,
        fi: &FileInfo,
        files: &[FileInfo],
        disks: &[Option<DiskStore>],
@@ -503,7 +500,13 @@ impl SetDisks {
            return Ok(None);
        }

-        let erasure = erasure_cache.get_for_file_info(fi)?;
+        let erasure = coding::Erasure::try_new_with_options(
+            fi.erasure.data_blocks,
+            fi.erasure.parity_blocks,
+            fi.erasure.block_size,
+            fi.uses_legacy_checksum,
+        )
+        .map_err(Error::from)?;

        let checksum_info = fi.erasure.get_checksum_info(part.number);
        let checksum_algo = if fi.uses_legacy_checksum && checksum_info.algorithm == HashAlgorithm::HighwayHash256S {
@@ -631,7 +634,6 @@ impl SetDisks {
        // &self,
        bucket: &str,
        object: &str,
-        erasure_cache: Arc<ErasureCache>,
        offset: usize,
        length: i64,
        writer: &mut W,
@@ -726,7 +728,13 @@ impl SetDisks {
            object, offset, length, end_offset, part_index, last_part_index, last_part_relative_offset, "Multipart read bounds"
        );

-        let erasure = erasure_cache.get_for_file_info(&fi)?;
+        let erasure = coding::Erasure::try_new_with_options(
+            fi.erasure.data_blocks,
+            fi.erasure.parity_blocks,
+            fi.erasure.block_size,
+            fi.uses_legacy_checksum,
+        )
+        .map_err(Error::from)?;

        let part_indices: Vec<usize> = (part_index..=last_part_index).collect();
        debug!(bucket, object, ?part_indices, "Multipart part indices to stream");
@@ -1160,7 +1168,6 @@ impl SetDisks {
    pub(super) async fn get_object_decode_reader_with_fileinfo(
        bucket: &str,
        object: &str,
-        erasure_cache: Arc<ErasureCache>,
        fi: &FileInfo,
        files: &[FileInfo],
        disks: &[Option<DiskStore>],
@@ -1171,7 +1178,14 @@ impl SetDisks {
        metrics_size_bucket: &'static str,
        prefer_data_blocks_first_reader_setup: bool,
    ) -> Result<GetCodecStreamingReaderBuildOutcome> {
-        let erasure = erasure_cache.get_for_file_info(fi)?;
+        let erasure = coding::Erasure::try_new_with_options(
+            fi.erasure.data_blocks,
+            fi.erasure.parity_blocks,
+            fi.erasure.block_size,
+            fi.uses_legacy_checksum,
+        )
+        .map_err(Error::from)?;
+
        let (disks, files) = Self::shuffle_disks_and_parts_metadata_by_index(disks, files, fi);

        if fi.parts.len() == 1 {
@@ -1558,7 +1572,7 @@ struct LazyCodecPartContext {
    fi: FileInfo,
    files: Vec<FileInfo>,
    disks: Vec<Option<DiskStore>>,
-    erasure: Arc<coding::Erasure>,
+    erasure: coding::Erasure,
    skip_verify_bitrot: bool,
    metrics_object_class: &'static str,
    metrics_size_bucket: &'static str,
@@ -1812,9 +1826,6 @@ fn get_object_metadata_cache_request_bypass_reason(bucket: &str, opts: &ObjectOp
    if opts.part_number.is_some() {
        return Some(GET_METADATA_CACHE_REASON_PART_NUMBER);
    }
-    if opts.include_part_checksums {
-        return Some(GET_METADATA_CACHE_REASON_PART_CHECKSUMS);
-    }
    if opts.data_movement {
        return Some(GET_METADATA_CACHE_REASON_DATA_MOVEMENT);
    }
@@ -2042,7 +2053,6 @@ mod metadata_cache_tests {
        let err = SetDisks::get_object_with_fileinfo(
            "bucket",
            "object",
-            Arc::new(ErasureCache::new()),
            0,
            1,
            &mut output,
@@ -2073,7 +2083,6 @@ mod metadata_cache_tests {
        let err = SetDisks::get_object_with_fileinfo(
            bucket,
            object,
-            Arc::new(ErasureCache::new()),
            2,
            1,
            &mut output,
@@ -2097,7 +2106,6 @@ mod metadata_cache_tests {
        let err = SetDisks::get_object_with_fileinfo(
            bucket,
            object,
-            Arc::new(ErasureCache::new()),
            usize::MAX,
            1,
            &mut output,
@@ -2119,7 +2127,6 @@ mod metadata_cache_tests {
        let err = SetDisks::get_object_with_fileinfo(
            bucket,
            object,
-            Arc::new(ErasureCache::new()),
            1,
            1,
            &mut output,
@@ -2143,7 +2150,6 @@ mod metadata_cache_tests {
        let err = SetDisks::get_object_with_fileinfo(
            bucket,
            object,
-            Arc::new(ErasureCache::new()),
            0,
            1,
            &mut output,
@@ -2181,7 +2187,6 @@ mod metadata_cache_tests {
        SetDisks::get_object_with_fileinfo(
            bucket,
            object,
-            Arc::new(ErasureCache::new()),
            0,
            0,
            &mut output,
@@ -2214,7 +2219,6 @@ mod metadata_cache_tests {
        let err = SetDisks::get_object_with_fileinfo(
            bucket,
            object,
-            Arc::new(ErasureCache::new()),
            0,
            1,
            &mut output,
@@ -2493,16 +2497,6 @@ mod metadata_cache_tests {
            Some(GET_METADATA_CACHE_REASON_PART_NUMBER)
        );

-        opts = ObjectOptions {
-            include_part_checksums: true,
-            ..Default::default()
-        };
-        assert!(!is_get_object_metadata_cache_request_eligible("bucket", &opts, true));
-        assert_eq!(
-            get_object_metadata_cache_request_bypass_reason("bucket", &opts, true),
-            Some(GET_METADATA_CACHE_REASON_PART_CHECKSUMS)
-        );
-
        opts = ObjectOptions {
            data_movement: true,
            ..Default::default()
@@ -2707,14 +2701,22 @@ mod metadata_cache_tests {
            .await
            .expect("fresh cache entry should be returned");

-        let returned = set
+        let (returned_fi, returned_parts_metadata, returned_online_disks) = set
            .get_object_fileinfo("bucket", "object", &ObjectOptions::default(), true, false)
            .await
            .expect("cache-backed metadata lookup should succeed");

        assert!(
-            returned.shared_entry().is_some_and(|value| Arc::ptr_eq(value, &cached)),
-            "cache hits must share the complete metadata snapshot"
+            matches!(returned_fi, GetObjectMetadata::Shared(ref value) if Arc::ptr_eq(value, &cached.fi)),
+            "cache hits must share FileInfo ownership"
+        );
+        assert!(
+            matches!(returned_parts_metadata, GetObjectMetadata::Shared(ref value) if Arc::ptr_eq(value, &cached.parts_metadata)),
+            "cache hits must share the metadata vector"
+        );
+        assert!(
+            matches!(returned_online_disks, GetObjectMetadata::Shared(ref value) if Arc::ptr_eq(value, &cached.online_disks)),
+            "cache hits must share the online-disk vector"
        );
    }

@@ -2757,9 +2759,9 @@ mod metadata_cache_tests {
                ),
                Arc::new(GetObjectMetadataCacheEntry {
                    created_at: Instant::now(),
-                    fi: fi.clone(),
-                    parts_metadata: vec![fi],
-                    online_disks: vec![None],
+                    fi: Arc::new(fi.clone()),
+                    parts_metadata: Arc::new(vec![fi]),
+                    online_disks: Arc::new(vec![None]),
                    read_quorum: 1,
                }),
            )
@@ -2853,12 +2855,13 @@ mod metadata_cache_tests {
        barrier.wait_until_paused().await;
        set.invalidate_get_object_metadata_cache(bucket, object).await;
        barrier.release();
-        let snapshot = read
+        let (fi, parts_metadata, online_disks) = read
            .await
            .expect("metadata read task should not panic")
            .expect("metadata fanout should still return its selected FileInfo");
-        assert!(snapshot.owned.is_some());
-        assert!(snapshot.has_valid_representation());
+        assert!(matches!(fi, GetObjectMetadata::Owned(_)));
+        assert!(matches!(parts_metadata, GetObjectMetadata::Owned(_)));
+        assert!(matches!(online_disks, GetObjectMetadata::Owned(_)));

        assert!(
            set.get_object_metadata_cache
@@ -2905,9 +2908,9 @@ mod metadata_cache_tests {
        let key = GetObjectMetadataCacheKey::new("bucket", "object", generation);
        let entry = Arc::new(GetObjectMetadataCacheEntry {
            created_at: Instant::now(),
-            fi: fi.clone(),
-            parts_metadata: vec![fi],
-            online_disks: Vec::new(),
+            fi: Arc::new(fi.clone()),
+            parts_metadata: Arc::new(vec![fi]),
+            online_disks: Arc::new(Vec::new()),
            read_quorum: 0,
        });

@@ -3015,9 +3018,9 @@ mod metadata_cache_tests {
        let entry = |fi: FileInfo| {
            Arc::new(GetObjectMetadataCacheEntry {
                created_at: Instant::now(),
-                parts_metadata: vec![fi.clone()],
-                fi,
-                online_disks: Vec::new(),
+                parts_metadata: Arc::new(vec![fi.clone()]),
+                fi: Arc::new(fi),
+                online_disks: Arc::new(Vec::new()),
                read_quorum: 0,
            })
        };
@@ -4080,8 +4083,8 @@ mod tests {
        get_codec_streaming_reader_gate(
            CODEC_STREAMING_TEST_BUCKET,
            CODEC_STREAMING_TEST_OBJECT,
+            range,
            None,
-            classify_get_codec_streaming_object_class(range, object_info, fi),
            object_info,
            fi,
            lock_optimization_enabled,
@@ -4098,8 +4101,8 @@ mod tests {
        get_codec_streaming_reader_gate(
            CODEC_STREAMING_TEST_BUCKET,
            CODEC_STREAMING_TEST_OBJECT,
+            range,
            part_number,
-            classify_get_codec_streaming_object_class(range, object_info, fi),
            object_info,
            fi,
            lock_optimization_enabled,
@@ -4119,7 +4122,6 @@ mod tests {
        let result = SetDisks::get_object_decode_reader_with_fileinfo(
            CODEC_STREAMING_TEST_BUCKET,
            CODEC_STREAMING_TEST_OBJECT,
-            Arc::new(ErasureCache::new()),
            &fi,
            &[],
            &[],
@@ -4142,7 +4144,6 @@ mod tests {
        let invalid_size = SetDisks::get_object_decode_reader_with_fileinfo(
            CODEC_STREAMING_TEST_BUCKET,
            CODEC_STREAMING_TEST_OBJECT,
-            Arc::new(ErasureCache::new()),
            &single_part,
            &[],
            &[],
@@ -4163,7 +4164,6 @@ mod tests {
            SetDisks::get_object_decode_reader_with_fileinfo(
                CODEC_STREAMING_TEST_BUCKET,
                CODEC_STREAMING_TEST_OBJECT,
-                Arc::new(ErasureCache::new()),
                &multipart,
                &[],
                &[],
@@ -4188,7 +4188,6 @@ mod tests {
            SetDisks::get_object_decode_reader_with_fileinfo(
                CODEC_STREAMING_TEST_BUCKET,
                CODEC_STREAMING_TEST_OBJECT,
-                Arc::new(ErasureCache::new()),
                &multipart,
                &[],
                &[],
@@ -4217,7 +4216,6 @@ mod tests {
                SetDisks::get_object_decode_reader_with_fileinfo(
                    CODEC_STREAMING_TEST_BUCKET,
                    CODEC_STREAMING_TEST_OBJECT,
-                    Arc::new(ErasureCache::new()),
                    &multipart,
                    &[],
                    &[],
@@ -4271,7 +4269,6 @@ mod tests {
                SetDisks::get_object_decode_reader_with_fileinfo(
                    CODEC_STREAMING_TEST_BUCKET,
                    CODEC_STREAMING_TEST_OBJECT,
-                    Arc::new(ErasureCache::new()),
                    &fi,
                    &files,
                    &disks,
@@ -4325,7 +4322,6 @@ mod tests {
            SetDisks::get_object_decode_reader_with_fileinfo(
                CODEC_STREAMING_TEST_BUCKET,
                CODEC_STREAMING_TEST_OBJECT,
-                Arc::new(ErasureCache::new()),
                &fi,
                &files,
                &disks,
@@ -4370,7 +4366,6 @@ mod tests {
        SetDisks::get_object_with_fileinfo(
            CODEC_STREAMING_TEST_BUCKET,
            CODEC_STREAMING_TEST_OBJECT,
-            Arc::new(ErasureCache::new()),
            0,
            part_data.len() as i64,
            &mut output,
@@ -4833,114 +4828,6 @@ mod tests {
        .await
    }

-    async fn encoded_inline_blocks(blocks: &[&[u8]], shard_size: usize, hash_algo: HashAlgorithm) -> Bytes {
-        let mut writer = BitrotWriter::new(Cursor::new(Vec::new()), shard_size, hash_algo);
-        for block in blocks {
-            writer.write(block).await.expect("test block should be encoded");
-        }
-        Bytes::from(writer.into_inner().into_inner())
-    }
-
-    fn assert_reader_shares_inline_allocation(reader: &ObjectBitrotReader, source: &Bytes) {
-        let reader_bytes = reader
-            .inner_ref()
-            .inline_bytes()
-            .expect("inline scheduler should retain an in-memory Bytes source");
-        assert_eq!(
-            reader_bytes.as_ptr(),
-            source.as_ptr(),
-            "the scheduler must clone Bytes ownership instead of copying the inline shard payload"
-        );
-    }
-
-    #[tokio::test]
-    async fn inline_range_scheduler_shares_bytes_and_rejects_bitrot_mismatch() {
-        const SHARD_SIZE: usize = 16;
-        let hash_algo = HashAlgorithm::HighwayHash256S;
-        let first = [b'a'; SHARD_SIZE];
-        let second = [b'b'; SHARD_SIZE];
-        let mut source = encoded_inline_blocks(&[&first, &second], SHARD_SIZE, hash_algo.clone()).await;
-        let second_payload = hash_algo.size() * 2 + SHARD_SIZE;
-        source = {
-            let mut corrupt = source.to_vec();
-            corrupt[second_payload] ^= 0xff;
-            Bytes::from(corrupt)
-        };
-        let files = vec![encoded_reader_setup_fileinfo(Some(source.to_vec()))];
-        let source = files[0].data.clone().expect("inline shard should exist");
-        let disks = vec![None];
-
-        let mut setup = create_bitrot_readers_until_quorum_with_preference(
-            &files,
-            &disks,
-            "bucket",
-            "object",
-            1,
-            SHARD_SIZE,
-            SHARD_SIZE,
-            SHARD_SIZE,
-            hash_algo,
-            false,
-            false,
-            1,
-            0,
-            BitrotReaderSetupMode::ReadQuorum,
-            true,
-            None,
-            None,
-        )
-        .await;
-        let mut reader = setup.readers[0].take().expect("range reader should be ready");
-        assert_reader_shares_inline_allocation(&reader, &source);
-
-        let err = reader
-            .read(&mut [0; SHARD_SIZE])
-            .await
-            .expect_err("corrupt ranged inline block must fail bitrot verification");
-        assert_eq!(err.kind(), ErrorKind::InvalidData);
-    }
-
-    #[tokio::test]
-    async fn inline_part_scheduler_shares_bytes_and_rejects_bitrot_mismatch() {
-        const SHARD_SIZE: usize = 16;
-        let hash_algo = HashAlgorithm::HighwayHash256S;
-        let block = [b'p'; SHARD_SIZE];
-        let encoded = encoded_inline_blocks(&[&block], SHARD_SIZE, hash_algo.clone()).await;
-        let mut corrupt = encoded.to_vec();
-        corrupt[hash_algo.size()] ^= 0xff;
-        let files = vec![encoded_reader_setup_fileinfo(Some(corrupt))];
-        let source = files[0].data.clone().expect("inline shard should exist");
-        let disks = vec![None];
-
-        let mut setup = create_bitrot_readers_until_quorum_all_shards(
-            &files,
-            &disks,
-            "bucket",
-            "object",
-            7,
-            0,
-            SHARD_SIZE,
-            SHARD_SIZE,
-            hash_algo,
-            false,
-            false,
-            1,
-            0,
-            BitrotReaderSetupMode::VerifyReconstruction,
-            None,
-            None,
-        )
-        .await;
-        let mut reader = setup.readers[0].take().expect("part reader should be ready");
-        assert_reader_shares_inline_allocation(&reader, &source);
-
-        let err = reader
-            .read(&mut [0; SHARD_SIZE])
-            .await
-            .expect_err("corrupt inline part must fail bitrot verification");
-        assert_eq!(err.kind(), ErrorKind::InvalidData);
-    }
-
    async fn decode_codec_data_blocks_first_setup(
        erasure: coding::Erasure,
        data: &[u8],
@@ -5641,63 +5528,6 @@ mod tests {
        });
    }

-    #[test]
-    fn codec_streaming_config_cache_loads_once() {
-        use std::cell::Cell;
-
-        let loads = Cell::new(0);
-        let expected = GetCodecStreamingConfig {
-            enabled: true,
-            rollout: GetCodecStreamingRollout::Off,
-            rollout_pct: 100,
-            body_compat_confirmed: true,
-            header_compat_confirmed: true,
-            engine: GetCodecStreamingEngine::Legacy,
-            min_size: DEFAULT_RUSTFS_GET_CODEC_STREAMING_MIN_SIZE,
-        };
-
-        for _ in 0..3 {
-            assert_eq!(
-                get_codec_streaming_config_cached_core(|| {
-                    loads.set(loads.get() + 1);
-                    expected
-                }),
-                expected
-            );
-        }
-        assert_eq!(loads.get(), 1, "production config cache must not reload env per GET");
-    }
-
-    #[test]
-    fn codec_streaming_config_loader_preserves_all_gate_env_overrides() {
-        temp_env::with_vars(
-            [
-                (ENV_RUSTFS_GET_CODEC_STREAMING_ENABLE, Some("false")),
-                (ENV_RUSTFS_GET_CODEC_STREAMING_ENGINE, Some(GET_CODEC_STREAMING_ENGINE_RUSTFS)),
-                (ENV_RUSTFS_GET_CODEC_STREAMING_ROLLOUT, Some("production")),
-                (ENV_RUSTFS_GET_CODEC_STREAMING_ROLLOUT_PCT, Some("37")),
-                (ENV_RUSTFS_GET_CODEC_STREAMING_BODY_COMPAT_CONFIRMED, Some("false")),
-                (ENV_RUSTFS_GET_CODEC_STREAMING_HEADER_COMPAT_CONFIRMED, Some("false")),
-                (ENV_RUSTFS_GET_CODEC_STREAMING_MIN_SIZE, None::<&str>),
-                (ENV_RUSTFS_GET_CODEC_STREAMING_RUSTFS_MIN_SIZE, Some("262144")),
-            ],
-            || {
-                assert_eq!(
-                    load_get_codec_streaming_config(),
-                    GetCodecStreamingConfig {
-                        enabled: false,
-                        rollout: GetCodecStreamingRollout::On,
-                        rollout_pct: 37,
-                        body_compat_confirmed: false,
-                        header_compat_confirmed: false,
-                        engine: GetCodecStreamingEngine::Rustfs,
-                        min_size: 262144,
-                    }
-                );
-            },
-        );
-    }
-
    #[test]
    fn codec_streaming_default_min_size_meets_direct_memory_ceiling() {
        for engine in [None, Some(GET_CODEC_STREAMING_ENGINE_RUSTFS)] {
@@ -48,23 +48,6 @@ impl RestoreCleanupIdentity {
    }
 }

-fn ensure_restore_metadata_lock_held(bucket: &str, object: &str, opts: &ObjectOptions, mode: &'static str) -> Result<()> {
-    if opts
-        .namespace_lock_fence
-        .as_ref()
-        .is_some_and(NamespaceLockFence::is_lock_lost)
-    {
-        return Err(StorageError::NamespaceLockQuorumUnavailable {
-            mode,
-            bucket: bucket.to_string(),
-            object: object.to_string(),
-            required: 1,
-            achieved: 0,
-        });
-    }
-    Ok(())
-}
-
 impl SetDisks {
    pub(super) async fn finalize_restore_metadata(
        &self,
@@ -92,20 +75,18 @@ impl SetDisks {
            version_id,
            versioned: opts.versioned,
            version_suspended: opts.version_suspended,
-            include_part_checksums: true,
            ..Default::default()
        };
-        let (mut fi, _, disks) = self
+        let (fi, _, disks) = self
            .get_object_fileinfo_gated(bucket, object, &read_opts, false, false)
-            .await?
-            .into_owned();
+            .await?;
+        let mut fi = fi.into_owned();
        if let Some(expected_operation_id) = expected_operation_id {
            require_restore_operation_id(&fi.metadata, expected_operation_id)?;
        }
        if !expected.matches_file_info(&fi, &expected_etag) {
            return Err(Error::other("restored object changed before restore metadata finalization"));
        }
-        ensure_restore_metadata_lock_held(bucket, object, opts, "restore_finalize_metadata")?;
        let restore_expiry =
            lifecycle::expected_expiry_time(OffsetDateTime::now_utc(), opts.transition.restore_request.days.unwrap_or(1));
        fi.metadata.insert(
@@ -161,13 +142,12 @@ impl SetDisks {
            version_id,
            versioned: opts.versioned,
            version_suspended: opts.version_suspended,
-            include_part_checksums: true,
            ..Default::default()
        };
-        let (mut fi, _, disks) = self
+        let (fi, _, disks) = self
            .get_object_fileinfo_gated(bucket, object, &read_opts, false, false)
-            .await?
-            .into_owned();
+            .await?;
+        let mut fi = fi.into_owned();
        if let Some(expected_operation_id) = expected_operation_id {
            match restore_operation_id_from_metadata(&fi.metadata)? {
                Some(actual_operation_id) if actual_operation_id == expected_operation_id => {}
@@ -177,7 +157,6 @@ impl SetDisks {
        if !expected.matches_file_info(&fi, &expected_etag) {
            return Ok(());
        }
-        ensure_restore_metadata_lock_held(bucket, object, opts, "restore_cleanup_metadata")?;
        fi.metadata.remove(X_AMZ_RESTORE.as_str());
        fi.metadata.remove(AMZ_RESTORE_EXPIRY_DAYS);
        fi.metadata.remove(AMZ_RESTORE_REQUEST_DATE);
@@ -16,14 +16,6 @@ use crate::diagnostics::get::{
    GET_SHARD_READ_COST_LOCAL, GET_SHARD_READ_COST_REMOTE, GET_SHARD_READ_COST_SAME_NODE, GET_SHARD_READ_COST_UNKNOWN,
 };
 use crate::disk::error::Error;
-use crate::layout::disks_layout::MAX_ERASURE_SET_DRIVE_COUNT;
-use smallvec::SmallVec;
-
-/// Generic codec callers may exceed the production set limit; `SmallVec` then
-/// spills without changing slot semantics.
-pub(crate) const INLINE_SHARD_SLOTS: usize = MAX_ERASURE_SET_DRIVE_COUNT;
-pub(crate) type ShardBuffers = SmallVec<[Option<Vec<u8>>; INLINE_SHARD_SLOTS]>;
-pub(crate) type ShardErrors = SmallVec<[Option<Error>; INLINE_SHARD_SLOTS]>;

 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub(crate) enum ShardReadCost {
@@ -51,137 +43,202 @@ impl ShardReadCost {
    }
 }

+#[derive(Debug, Clone, PartialEq, Eq)]
+pub(crate) struct ShardSlot {
+    index: usize,
+    read_cost: ShardReadCost,
+    data: Option<Vec<u8>>,
+    error: Option<Error>,
+}
+
+impl ShardSlot {
+    pub(crate) fn new(index: usize, data: Option<Vec<u8>>, error: Option<Error>) -> Self {
+        Self::with_read_cost(index, ShardReadCost::Unknown, data, error)
+    }
+
+    pub(crate) fn with_read_cost(index: usize, read_cost: ShardReadCost, data: Option<Vec<u8>>, error: Option<Error>) -> Self {
+        Self {
+            index,
+            read_cost,
+            data,
+            error,
+        }
+    }
+
+    pub(crate) fn data(index: usize, data: Vec<u8>) -> Self {
+        Self::new(index, Some(data), None)
+    }
+
+    pub(crate) fn data_with_read_cost(index: usize, read_cost: ShardReadCost, data: Vec<u8>) -> Self {
+        Self::with_read_cost(index, read_cost, Some(data), None)
+    }
+
+    pub(crate) fn missing(index: usize, error: Error) -> Self {
+        Self::new(index, None, Some(error))
+    }
+
+    pub(crate) fn missing_with_read_cost(index: usize, read_cost: ShardReadCost, error: Error) -> Self {
+        Self::with_read_cost(index, read_cost, None, Some(error))
+    }
+
+    pub(crate) fn index(&self) -> usize {
+        self.index
+    }
+
+    pub(crate) fn read_cost(&self) -> ShardReadCost {
+        self.read_cost
+    }
+
+    pub(crate) fn has_data(&self) -> bool {
+        self.data.is_some()
+    }
+
+    pub(crate) fn data_bytes(&self) -> Option<&[u8]> {
+        self.data.as_deref()
+    }
+
+    pub(crate) fn error(&self) -> Option<&Error> {
+        self.error.as_ref()
+    }
+}
+
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub(crate) struct StripeReadState {
-    shards: ShardBuffers,
-    errors: ShardErrors,
+    slots: Vec<ShardSlot>,
    read_quorum: usize,
 }

 impl StripeReadState {
-    #[cfg(test)]
+    pub(crate) fn new(slots: Vec<ShardSlot>, read_quorum: usize) -> Self {
+        Self { slots, read_quorum }
+    }
+
    pub(crate) fn from_parts(shards: Vec<Option<Vec<u8>>>, errors: Vec<Option<Error>>, read_quorum: usize) -> Self {
-        let mut shards = SmallVec::from_vec(shards);
-        let mut errors = SmallVec::from_vec(errors);
+        Self::from_parts_with_read_costs(shards, errors, &[], read_quorum)
+    }
+
+    pub(crate) fn from_parts_with_read_costs<S, E>(shards: S, errors: E, read_costs: &[ShardReadCost], read_quorum: usize) -> Self
+    where
+        S: IntoIterator<Item = Option<Vec<u8>>>,
+        S::IntoIter: ExactSizeIterator,
+        E: IntoIterator<Item = Option<Error>>,
+        E::IntoIter: ExactSizeIterator,
+    {
+        let mut shards = shards.into_iter();
+        let mut errors = errors.into_iter();
        let slot_count = shards.len().max(errors.len());
-        shards.resize_with(slot_count, || None);
-        errors.resize_with(slot_count, || None);
-        Self {
-            shards,
-            errors,
-            read_quorum,
+        let mut slots = Vec::with_capacity(slot_count);
+        for index in 0..slot_count {
+            let read_cost = read_costs.get(index).copied().unwrap_or(ShardReadCost::Unknown);
+            slots.push(ShardSlot::with_read_cost(
+                index,
+                read_cost,
+                shards.next().flatten(),
+                errors.next().flatten(),
+            ));
        }
-    }
-
-    pub(crate) fn with_slot_count(slot_count: usize, read_quorum: usize) -> Self {
-        let mut state = Self {
-            shards: SmallVec::new(),
-            errors: SmallVec::new(),
-            read_quorum,
-        };
-        state.reset(slot_count, read_quorum);
-        state
-    }
-
-    pub(crate) fn reset(&mut self, slot_count: usize, read_quorum: usize) {
-        self.shards.clear();
-        self.shards.resize_with(slot_count, || None);
-        self.errors.clear();
-        self.errors.resize_with(slot_count, || None);
-        self.read_quorum = read_quorum;
+        Self::new(slots, read_quorum)
    }

    pub(crate) fn available_shards(&self) -> usize {
-        self.shards.iter().filter(|shard| shard.is_some()).count()
+        self.slots.iter().filter(|slot| slot.has_data()).count()
    }

    pub(crate) fn can_decode(&self) -> bool {
        self.available_shards() >= self.read_quorum
    }

-    pub(crate) fn is_empty(&self) -> bool {
-        self.shards.is_empty()
+    pub(crate) fn slots(&self) -> &[ShardSlot] {
+        &self.slots
    }

-    pub(crate) fn data_bytes(&self, index: usize) -> Option<&[u8]> {
-        self.shards.get(index).and_then(Option::as_deref)
-    }
-
-    #[cfg(test)]
-    pub(crate) fn error(&self, index: usize) -> Option<&Error> {
-        self.errors.get(index).and_then(Option::as_ref)
+    pub(crate) fn slot_by_index(&self, index: usize) -> Option<&ShardSlot> {
+        if let Some(slot) = self.slots.get(index)
+            && slot.index == index
+        {
+            return Some(slot);
+        }
+        self.slots.iter().find(|slot| slot.index == index)
    }

    pub(crate) fn data_shards_complete(&self, data_shards: usize) -> bool {
-        self.shards.len() >= data_shards && self.shards.iter().take(data_shards).all(Option::is_some)
+        (0..data_shards).all(|index| self.slot_by_index(index).is_some_and(ShardSlot::has_data))
    }

-    pub(crate) fn parts_mut(&mut self) -> (&mut ShardBuffers, &mut ShardErrors) {
-        (&mut self.shards, &mut self.errors)
-    }
-
-    pub(crate) fn shards_mut(&mut self) -> &mut ShardBuffers {
-        &mut self.shards
-    }
-
-    pub(crate) fn into_parts(self) -> (ShardBuffers, ShardErrors) {
-        (self.shards, self.errors)
-    }
-
-    #[cfg(test)]
-    pub(crate) fn scratch_storage(&self) -> (*const Option<Vec<u8>>, *const Option<Error>, bool, bool) {
-        (self.shards.as_ptr(), self.errors.as_ptr(), self.shards.spilled(), self.errors.spilled())
-    }
-
-    #[cfg(test)]
-    pub(crate) fn shard_allocation(&self, index: usize) -> Option<(*const u8, usize)> {
-        self.shards
-            .get(index)
-            .and_then(|shard| shard.as_ref().map(|shard| (shard.as_ptr(), shard.capacity())))
+    pub(crate) fn into_parts(self) -> (Vec<Option<Vec<u8>>>, Vec<Option<Error>>) {
+        let part_count = self.slots.iter().map(|slot| slot.index).max().map_or(0, |index| index + 1);
+        let mut shards = Vec::with_capacity(part_count);
+        shards.resize_with(part_count, || None);
+        let mut errors = Vec::with_capacity(part_count);
+        errors.resize_with(part_count, || None);
+        for slot in self.slots {
+            shards[slot.index] = slot.data;
+            errors[slot.index] = slot.error;
+        }
+        (shards, errors)
    }
 }

 #[async_trait::async_trait]
 pub(crate) trait ShardStripeSource: Send {
-    async fn read_next_stripe(&mut self) -> Box<StripeReadState>;
-
-    fn recycle_stripe(&mut self, _state: Box<StripeReadState>) {}
+    async fn read_next_stripe(&mut self) -> StripeReadState;
 }

 #[cfg(test)]
 mod tests {
    use super::*;
-    use std::mem::size_of;

    #[test]
-    fn stripe_scratch_capacity_matches_the_production_set_limit() {
-        type OversizedShardBuffers = SmallVec<[Option<Vec<u8>>; 32]>;
-        type OversizedShardErrors = SmallVec<[Option<Error>; 32]>;
-
-        assert_eq!(INLINE_SHARD_SLOTS, MAX_ERASURE_SET_DRIVE_COUNT);
-        assert!(size_of::<ShardBuffers>() < size_of::<OversizedShardBuffers>());
-        assert!(size_of::<ShardErrors>() < size_of::<OversizedShardErrors>());
-    }
-
-    #[test]
-    fn stripe_read_state_tracks_decode_quorum_and_slot_access() {
-        let state =
-            StripeReadState::from_parts(vec![Some(vec![1]), None, Some(vec![2])], vec![None, Some(Error::FileNotFound), None], 2);
+    fn stripe_read_state_tracks_decode_quorum() {
+        let state = StripeReadState::new(
+            vec![
+                ShardSlot::data_with_read_cost(0, ShardReadCost::Local, vec![1]),
+                ShardSlot::missing_with_read_cost(1, ShardReadCost::Remote, Error::FileNotFound),
+                ShardSlot::data_with_read_cost(2, ShardReadCost::SameNode, vec![2]),
+            ],
+            2,
+        );

        assert_eq!(state.available_shards(), 2);
        assert!(state.can_decode());
-        assert_eq!(state.data_bytes(0), Some(&[1][..]));
-        assert_eq!(state.error(1), Some(&Error::FileNotFound));
+        assert_eq!(state.slots()[1].index(), 1);
+        assert_eq!(state.slots()[0].read_cost(), ShardReadCost::Local);
+        assert!(state.slots()[2].read_cost().is_low_cost());
    }

    #[test]
    fn stripe_read_state_preserves_shards_and_errors() {
-        let state = StripeReadState::from_parts(vec![Some(vec![1, 2, 3]), None], vec![None, Some(Error::FileCorrupt)], 2);
+        let state = StripeReadState::new(vec![ShardSlot::missing(1, Error::FileCorrupt), ShardSlot::data(0, vec![1, 2, 3])], 2);

        assert!(!state.can_decode());
        let (shards, errors) = state.into_parts();
-        assert_eq!(shards.as_slice(), &[Some(vec![1, 2, 3]), None]);
-        assert_eq!(errors.as_slice(), &[None, Some(Error::FileCorrupt)]);
+        assert_eq!(shards, vec![Some(vec![1, 2, 3]), None]);
+        assert_eq!(errors, vec![None, Some(Error::FileCorrupt)]);
+    }
+
+    #[test]
+    fn stripe_read_state_builds_slots_from_parallel_reader_parts() {
+        let state =
+            StripeReadState::from_parts(vec![Some(vec![1]), None, Some(vec![3])], vec![None, Some(Error::FileNotFound)], 2);
+
+        assert!(state.can_decode());
+        assert_eq!(state.slots()[1].index(), 1);
+        assert_eq!(state.slots()[1].error(), Some(&Error::FileNotFound));
+    }
+
+    #[test]
+    fn stripe_read_state_preserves_read_cost_hints() {
+        let state = StripeReadState::from_parts_with_read_costs(
+            vec![Some(vec![1]), None, Some(vec![3])],
+            vec![None, Some(Error::FileNotFound)],
+            &[ShardReadCost::Local, ShardReadCost::Remote, ShardReadCost::Unknown],
+            2,
+        );
+
+        assert_eq!(state.slots()[0].read_cost(), ShardReadCost::Local);
+        assert_eq!(state.slots()[1].read_cost(), ShardReadCost::Remote);
+        assert_eq!(state.slots()[2].read_cost(), ShardReadCost::Unknown);
+        assert_eq!(ShardReadCost::SameNode.as_str(), GET_SHARD_READ_COST_SAME_NODE);
    }

    #[test]
@@ -201,8 +258,8 @@ mod tests {
        let state = StripeReadState::from_parts(vec![Some(vec![1]), Some(vec![2]), None], Vec::new(), 2);

        assert!(state.data_shards_complete(2));
-        assert_eq!(state.data_bytes(0), Some(&[1][..]));
-        assert_eq!(state.data_bytes(1), Some(&[2][..]));
+        assert_eq!(state.slots()[0].data_bytes(), Some(&[1][..]));
+        assert_eq!(state.slot_by_index(1).and_then(ShardSlot::data_bytes), Some(&[2][..]));
    }

    #[test]
@@ -211,4 +268,12 @@ mod tests {

        assert!(!state.data_shards_complete(2));
    }
+
+    #[test]
+    fn stripe_read_state_finds_out_of_order_slots_by_index() {
+        let state = StripeReadState::new(vec![ShardSlot::data(2, vec![3]), ShardSlot::data(0, vec![1])], 2);
+
+        assert_eq!(state.slot_by_index(0).and_then(ShardSlot::data_bytes), Some(&[1][..]));
+        assert!(state.slot_by_index(1).is_none());
+    }
 }
@@ -161,10 +161,6 @@ impl BucketIncarnationFenceGuard {
    pub(crate) fn is_lock_lost(&self) -> bool {
        self.inner.as_ref().is_some_and(NamespaceLockGuard::is_lock_lost)
    }
-
-    pub(crate) fn namespace_lock_guard(&self) -> Option<&NamespaceLockGuard> {
-        self.inner.as_ref()
-    }
 }

 impl Drop for BucketIncarnationFenceGuard {
--- a/Show More
+++ b/Show More