# Documentation

Use the focused indexes rather than treating this directory as an unordered
collection:

- [Architecture knowledge base](architecture/README.md)
- [Testing references](testing/README.md)

## Operations

- [Table maintenance periodic queueing](operations/s3-tables-maintenance-scheduler.md) — opt-in scheduling, limits, worker handoff, and recovery.

For PUT cleanup admission, blocking-pool isolation, and optional CPU affinity,
see [PUT cleanup isolation](operations/put-cleanup-isolation.md).

- [External certificate issuance and TLS rotation](operations/tls-certificate-rotation.md) — publication, native reload, trust separation and failure handling.

- [Architecture guard troubleshooting](operations/architecture-guard-troubleshooting.md) — diagnose repository guard failures.
- [Logging governance](operations/logging-governance.md) — broad event audits, migrations, and guardrail changes.

- [Multipart upload memory diagnosis](operations/multipart-memory.md) — allocator attribution, Docker reproduction and sustained upload checks.

For the logical per-operation io_uring read cap, see
[io_uring read chunk size](operations/io-uring-read-chunks.md).

For bounded local read-backend startup and cancellation, see
[io_uring backend initialization](operations/io-uring-initialization.md).

For legacy protection assessment and bounded protected copies, see [Object integrity inventory, audit, and migration](operations/shard-integrity-audit.md).

For encrypted listing compatibility and older stored fingerprints, see
[Encrypted object ETags](operations/encrypted-etags.md).

For durable hard quota accounting, node-outage behavior, and fence protocol
upgrades, see [Durable hard quotas](operations/durable-quota-reservation-v2.md).

Operational runbooks live under [`operations/`](operations/). Replication
operators should start with:

| Runbook | Use it for |
|---|---|
| [Site replication operations](operations/site-replication-operations.md) | Health fields, pending operations, outage recovery, re-pair admission, IAM/SSE boundaries, and upgrades. |
| [Replication target check](operations/replication-check.md) | Validating an S3 destination and version fidelity before enabling replication. |
| [Replication object size limits](operations/replication-object-size-limits.md) | Multipart routing, large-object limits, and retry characteristics. |
| [Replication outbound transport](operations/replication-outbound-transport.md) | Integrity headers, generic target behavior, and transport knobs. |

For the erasure-coded cluster lifecycle (planning, parity and `EC:0`,
expansion, rebalance, decommission, heal, drive replacement, restart
recovery, and the `rc` CLI mapping), start with
[Cluster and erasure-coding lifecycle operations](operations/cluster-lifecycle-operations.md).

For concurrent bucket creation and deletion, see
[Bucket operation admission](operations/bucket-operation-admission.md).

For persisted administrator bucket tasks and bucket recreation, see
[Bucket heal recovery](operations/bucket-heal-recovery.md).

For interrupted object deletions and returning drives, see
[Delete transaction recovery](operations/delete-transaction-recovery.md).

For disk replacement across VM restarts and schema 5/6 maintenance migration,
see [Replacement generation recovery](operations/replacement-generation-recovery.md).

For historical GET timeouts during PUT or Heal, see
[Object lock contention diagnostics](operations/object-lock-contention.md).

Other runbooks remain grouped by filename in [`operations/`](operations/);
architecture pages link to the relevant runbook where a cross-boundary
procedure is required.

For storage dashboards, see [Storage metrics and observer selection](operations/storage-metrics.md):
drive ownership, snapshot freshness, counter queries, and rolling upgrades.

For per-bucket capacity and object counts, see [Bucket usage metrics](operations/bucket-usage-metrics.md):
OTLP export, cluster deduplication, accounting semantics, and scanner freshness.

For optional shard commitments, see [Independent shard integrity rollout](operations/shard-integrity-rollout.md):
activation, legacy repair results, multipart mode changes, and rollback limits.

For crates.io publication of workspace crates, see
[Workspace Cargo Publish](operations/cargo-publish-workspace.md): dependency
ordering, dry-run, publish, and failure handling.