feat(scanner): send scoped dirty usage acknowledgements

Bind dirty usage snapshots to storage owner and bucket incarnation IDs, then route completed dirty-scope scans through scoped peer acknowledgements instead of whole-generation clears.

Keep mixed-version and high-cardinality cases conservative by probing scoped ACK capability, capping automatic scoped activation to one protocol batch, and falling back to full-scan generation ACK when the scoped path is not clearly supported.

Co-Authored-By: heihutu <heihutu@gmail.com>

Co-Authored-By: zhi22915 <qiuzgang@gmail.com>

crates/ecstore/src/api/mod.rs

@@ -520,7 +520,8 @@ pub mod rpc {
     pub use crate::cluster::rpc::{
         AuthenticatedChannel, KMS_SIGNAL_SUBSYSTEM, LocalPeerS3Client, PEER_RESTDRY_RUN, PEER_RESTSIGNAL, PEER_RESTSUB_SYS,
         PeerRestClient, PeerS3Client, S3PeerSys, SERVICE_SIGNAL_REFRESH_CONFIG, SERVICE_SIGNAL_RELOAD_DYNAMIC,
-        ScannerBucketListing, ScannerPeerActivity, ScannerPeerDirtyUsageSnapshot, ScannerPublicationLease, TONIC_RPC_PREFIX,
+        ScannerBucketListing, ScannerDirtyUsageAcknowledgement, ScannerPeerActivity, ScannerPeerDirtyUsageBucket,
+        ScannerPeerDirtyUsageSnapshot, ScannerPublicationLease, ScannerScopedDirtyUsageAckEntry, TONIC_RPC_PREFIX,
         TonicInterceptor, build_put_file_auth_trailer, check_and_record_signed_rpc_nonce, decode_heal_bucket_rpc_options,
         encode_heal_bucket_rpc_options, gen_signature_headers, gen_tonic_replay_scope_headers, gen_tonic_signature_headers,
         gen_tonic_signature_interceptor, node_service_time_out_client, node_service_time_out_client_no_auth,

crates/ecstore/src/cluster/rpc/mod.rs

@@ -48,7 +48,8 @@ pub use internode_data_transport::build_internode_data_transport_from_env;
 pub(crate) use peer_rest_client::TierConfigReloadOutcome;
 pub use peer_rest_client::{
     KMS_SIGNAL_SUBSYSTEM, PEER_RESTDRY_RUN, PEER_RESTSIGNAL, PEER_RESTSUB_SYS, PeerRestClient, SERVICE_SIGNAL_REFRESH_CONFIG,
-    SERVICE_SIGNAL_RELOAD_DYNAMIC, ScannerPeerActivity, ScannerPeerDirtyUsageSnapshot, ScannerPublicationLease,
+    SERVICE_SIGNAL_RELOAD_DYNAMIC, ScannerDirtyUsageAcknowledgement, ScannerPeerActivity, ScannerPeerDirtyUsageBucket,
+    ScannerPeerDirtyUsageSnapshot, ScannerPublicationLease, ScannerScopedDirtyUsageAckEntry,
 };
 pub(crate) use peer_s3_client::heal_bucket_local_on_disks;
 pub use peer_s3_client::{

crates/ecstore/src/cluster/rpc/peer_rest_client.rs

@@ -49,10 +49,11 @@ use rustfs_protos::proto_gen::node_service::{
     LoadRebalanceMetaRequest, LoadServiceAccountRequest, LoadTransitionTierConfigRequest, LoadUserRequest,
     LocalStorageInfoRequest, Mss, ReloadPoolMetaRequest, ReloadSiteReplicationConfigRequest, ReplacementRecoveryStatusRequest,
     ScannerActivityRequest, ScannerActivityResponse, ScannerDirtyUsageSnapshotRequest, ScannerDirtyUsageSnapshotResponse,
-    ScannerPublicationLeaseReleaseRequest, ScannerPublicationLeaseRequest, ScannerPublicationLeaseResponse, ServerInfoRequest,
-    SignalServiceRequest, SignalServiceResponse, StartDecommissionRequest, StartProfilingRequest, StopRebalanceRequest,
-    TierDailyStatsRequest, TierMutationAbortRequest, TierMutationCommitRequest, TierMutationControlResponse,
-    TierMutationFailureClass, TierMutationPeerState, TierMutationPrepareRequest, node_service_client::NodeServiceClient,
+    ScannerPublicationLeaseReleaseRequest, ScannerPublicationLeaseRequest, ScannerPublicationLeaseResponse,
+    ScannerScopedDirtyUsageAckRequest, ScannerScopedDirtyUsageEntry, ServerInfoRequest, SignalServiceRequest,
+    SignalServiceResponse, StartDecommissionRequest, StartProfilingRequest, StopRebalanceRequest, TierDailyStatsRequest,
+    TierMutationAbortRequest, TierMutationCommitRequest, TierMutationControlResponse, TierMutationFailureClass,
+    TierMutationPeerState, TierMutationPrepareRequest, node_service_client::NodeServiceClient,
     tier_mutation_control_service_client::TierMutationControlServiceClient,
 };
 pub use rustfs_protos::{PEER_RESTDRY_RUN, PEER_RESTSIGNAL, PEER_RESTSUB_SYS};
@@ -92,6 +93,7 @@ const HEAL_CONTROL_PAYLOAD_MAX_SIZE: usize = 64 * 1024;
 const PEER_REST_RECOVERY_MAX_ATTEMPTS: u32 = 60;
 const PEER_REST_RECOVERY_MAX_BACKOFF: Duration = Duration::from_secs(30);
 const SCANNER_ACTIVITY_MAX_MESSAGE_SIZE: usize = 1024;
+const SCANNER_SCOPED_DIRTY_USAGE_STAGE_TIMEOUT: Duration = Duration::from_secs(5);
 /// Reserve time for the acquire response's network/clock uncertainty.  The
 /// server owns the real expiry; this local deadline is intentionally earlier
 /// so a coordinator never starts a bounded persistence operation at the edge
@@ -192,12 +194,102 @@ pub struct ScannerPeerActivity {
 
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub struct ScannerPeerDirtyUsageSnapshot {
+    pub owner_id: String,
     pub instance_id: String,
     pub generation: u64,
     pub pending_bucket_count: u64,
     pub protocol_version: u32,
     pub complete: bool,
-    pub buckets: BTreeMap<String, u64>,
+    pub buckets: BTreeMap<String, ScannerPeerDirtyUsageBucket>,
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub struct ScannerPeerDirtyUsageBucket {
+    pub bucket_incarnation: Uuid,
+    pub generation: u64,
+}
+
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct ScannerScopedDirtyUsageAckEntry {
+    pub bucket: String,
+    pub bucket_incarnation: Uuid,
+    pub generation: u64,
+}
+
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub enum ScannerDirtyUsageAcknowledgement {
+    Generation {
+        host: String,
+        instance_id: String,
+        generation: u64,
+    },
+    Scoped {
+        host: String,
+        owner_id: String,
+        instance_id: String,
+        entries: Vec<ScannerScopedDirtyUsageAckEntry>,
+    },
+}
+
+fn scanner_scoped_dirty_usage_ack_payloads(
+    owner_id: String,
+    instance_id: String,
+    probe_only: bool,
+    entries: Vec<ScannerScopedDirtyUsageAckEntry>,
+) -> Result<Vec<ScannerScopedDirtyUsageAckRequest>> {
+    use rustfs_protos::scoped_dirty_usage::*;
+
+    if entries.is_empty() {
+        return Err(Error::other("scoped dirty usage acknowledgement entries must be nonempty"));
+    }
+
+    let mut payloads = Vec::with_capacity(entries.len().div_ceil(SCOPED_DIRTY_USAGE_MAX_ENTRIES as usize));
+    let mut batch = Vec::with_capacity(SCOPED_DIRTY_USAGE_MAX_ENTRIES as usize);
+    for entry in entries {
+        batch.push(ScannerScopedDirtyUsageEntry {
+            bucket: entry.bucket,
+            bucket_incarnation: entry.bucket_incarnation.as_bytes().to_vec().into(),
+            generation: entry.generation,
+        });
+        if batch.len() == SCOPED_DIRTY_USAGE_MAX_ENTRIES as usize {
+            payloads.push(scanner_scoped_dirty_usage_ack_payload(
+                &owner_id,
+                &instance_id,
+                probe_only,
+                std::mem::take(&mut batch),
+            )?);
+        }
+    }
+    if !batch.is_empty() {
+        payloads.push(scanner_scoped_dirty_usage_ack_payload(&owner_id, &instance_id, probe_only, batch)?);
+    }
+
+    Ok(payloads)
+}
+
+fn scanner_scoped_dirty_usage_ack_payload(
+    owner_id: &str,
+    instance_id: &str,
+    probe_only: bool,
+    entries: Vec<ScannerScopedDirtyUsageEntry>,
+) -> Result<ScannerScopedDirtyUsageAckRequest> {
+    use rustfs_protos::scoped_dirty_usage::*;
+
+    let payload = ScannerScopedDirtyUsageAckRequest {
+        challenge: Uuid::new_v4().as_bytes().to_vec().into(),
+        protocol_version: SCOPED_DIRTY_USAGE_PROTOCOL_VERSION,
+        owner_id: owner_id.to_string(),
+        instance_id: instance_id.to_string(),
+        scope: SCOPED_DIRTY_USAGE_BUCKET_SCOPE,
+        probe_only,
+        entries,
+    };
+    canonical_scoped_dirty_usage_request(&payload).map_err(|err| Error::other(err.to_string()))?;
+    Ok(payload)
+}
+
+fn scanner_scoped_dirty_usage_ack_reconciled(activity: &ScannerPeerActivity, expected_instance_id: &str) -> bool {
+    activity.instance_id == expected_instance_id && activity.dirty_usage_pending == Some(false)
 }
 
 fn scanner_instance_id_is_valid(instance_id: &str) -> bool {
@@ -351,6 +443,11 @@ fn decode_scanner_dirty_usage_snapshot_with_verifier(
     if !scanner_instance_id_is_valid(&response.instance_id) {
         return Err(Error::other("peer returned an invalid scanner dirty usage snapshot instance ID"));
     }
+    let owner_id = Uuid::parse_str(&response.owner_id)
+        .ok()
+        .filter(|owner_id| !owner_id.is_nil())
+        .map(|owner_id| owner_id.to_string())
+        .ok_or_else(|| Error::other("peer returned an invalid scanner dirty usage snapshot owner"))?;
     if response.generation == u64::MAX {
         return Err(Error::other("peer scanner dirty usage snapshot exhausted its generation"));
     }
@@ -386,9 +483,14 @@ fn decode_scanner_dirty_usage_snapshot_with_verifier(
         if bucket.generation == 0 || bucket.generation > response.generation {
             return Err(Error::other("peer scanner dirty usage snapshot contains an invalid bucket generation"));
         }
+        Uuid::from_slice(bucket.bucket_incarnation.as_ref())
+            .ok()
+            .filter(|bucket_incarnation| !bucket_incarnation.is_nil())
+            .ok_or_else(|| Error::other("peer scanner dirty usage snapshot contains an invalid bucket incarnation"))?;
     }
 
     Ok(ScannerPeerDirtyUsageSnapshot {
+        owner_id,
         instance_id: response.instance_id,
         generation: response.generation,
         pending_bucket_count: response.pending_bucket_count,
@@ -397,7 +499,16 @@ fn decode_scanner_dirty_usage_snapshot_with_verifier(
         buckets: response
             .buckets
             .into_iter()
-            .map(|bucket| (bucket.bucket, bucket.generation))
+            .map(|bucket| {
+                (
+                    bucket.bucket,
+                    ScannerPeerDirtyUsageBucket {
+                        bucket_incarnation: Uuid::from_slice(bucket.bucket_incarnation.as_ref())
+                            .expect("bucket incarnation was validated"),
+                        generation: bucket.generation,
+                    },
+                )
+            })
             .collect(),
     })
 }
@@ -2077,19 +2188,10 @@ impl PeerRestClient {
         &self,
         owner_id: String,
         instance_id: String,
-        entries: Vec<rustfs_protos::proto_gen::node_service::ScannerScopedDirtyUsageEntry>,
+        entries: Vec<ScannerScopedDirtyUsageAckEntry>,
     ) -> Result<bool> {
         use rustfs_protos::scoped_dirty_usage::*;
-        let payload = rustfs_protos::proto_gen::node_service::ScannerScopedDirtyUsageAckRequest {
-            challenge: Uuid::new_v4().as_bytes().to_vec().into(),
-            protocol_version: SCOPED_DIRTY_USAGE_PROTOCOL_VERSION,
-            owner_id,
-            instance_id,
-            scope: SCOPED_DIRTY_USAGE_BUCKET_SCOPE,
-            probe_only: true,
-            entries,
-        };
-        let canonical = canonical_scoped_dirty_usage_request(&payload).map_err(|err| Error::other(err.to_string()))?;
+        let payloads = scanner_scoped_dirty_usage_ack_payloads(owner_id, instance_id, true, entries)?;
         self.finalize_result(
             async {
                 let mut client = super::client::scanner_control_time_out_client(
@@ -2097,26 +2199,106 @@ impl PeerRestClient {
                     TonicInterceptor::Signature(gen_tonic_signature_interceptor()),
                 )
                 .await?;
+                for payload in payloads {
+                    let canonical =
+                        canonical_scoped_dirty_usage_request(&payload).map_err(|err| Error::other(err.to_string()))?;
+                    let mut request = Request::new(payload.clone());
+                    set_tonic_canonical_body_digest(&mut request, &canonical)?;
+                    let response = client.scanner_scoped_dirty_usage_ack(request).await?.into_inner();
+                    let body = canonical_scoped_dirty_usage_response(&canonical, &response)
+                        .map_err(|_| Error::other("scoped dirty usage capability response is too large"))?;
+                    verify_tonic_rpc_response_proof(&body, response.response_proof.as_ref())?;
+                    if response.protocol_version != SCOPED_DIRTY_USAGE_PROTOCOL_VERSION
+                        || response.owner_id != payload.owner_id
+                        || response.instance_id != payload.instance_id
+                        || response.max_entries != SCOPED_DIRTY_USAGE_MAX_ENTRIES
+                        || response.max_request_bytes != SCOPED_DIRTY_USAGE_MAX_REQUEST_BYTES
+                        || response.cleared != 0
+                    {
+                        return Err(Error::other("scoped dirty usage capability response does not match request"));
+                    }
+                    if !response.supported {
+                        return Ok(false);
+                    }
+                }
+                Ok(true)
+            }
+            .await,
+        )
+        .await
+    }
+
+    pub async fn acknowledge_scanner_scoped_dirty_usage(
+        &self,
+        owner_id: String,
+        instance_id: String,
+        entries: Vec<ScannerScopedDirtyUsageAckEntry>,
+    ) -> Result<ScannerPeerActivity> {
+        use rustfs_protos::scoped_dirty_usage::*;
+        let payloads = scanner_scoped_dirty_usage_ack_payloads(owner_id, instance_id.clone(), false, entries)?;
+        let ack_attempt = async {
+            let mut client = super::client::scanner_control_time_out_client(
+                &self.grid_host,
+                TonicInterceptor::Signature(gen_tonic_signature_interceptor()),
+            )
+            .await?;
+            for payload in payloads {
+                let canonical = canonical_scoped_dirty_usage_request(&payload).map_err(|err| Error::other(err.to_string()))?;
                 let mut request = Request::new(payload.clone());
                 set_tonic_canonical_body_digest(&mut request, &canonical)?;
                 let response = client.scanner_scoped_dirty_usage_ack(request).await?.into_inner();
                 let body = canonical_scoped_dirty_usage_response(&canonical, &response)
-                    .map_err(|_| Error::other("scoped dirty usage capability response is too large"))?;
+                    .map_err(|_| Error::other("scoped dirty usage acknowledgement response is too large"))?;
                 verify_tonic_rpc_response_proof(&body, response.response_proof.as_ref())?;
                 if response.protocol_version != SCOPED_DIRTY_USAGE_PROTOCOL_VERSION
                     || response.owner_id != payload.owner_id
                     || response.instance_id != payload.instance_id
                     || response.max_entries != SCOPED_DIRTY_USAGE_MAX_ENTRIES
                     || response.max_request_bytes != SCOPED_DIRTY_USAGE_MAX_REQUEST_BYTES
-                    || response.cleared != 0
+                    || !response.supported
                 {
-                    return Err(Error::other("scoped dirty usage capability response does not match request"));
+                    return Err(Error::other("scoped dirty usage acknowledgement response does not match request"));
                 }
-                Ok(response.supported)
             }
-            .await,
-        )
-        .await
+            Ok(())
+        };
+        let result = match timeout(SCANNER_SCOPED_DIRTY_USAGE_STAGE_TIMEOUT, ack_attempt).await {
+            Ok(result) => self.finalize_result(result).await,
+            Err(_) => {
+                self.prepare_retry_with_timeout(SCANNER_SCOPED_DIRTY_USAGE_STAGE_TIMEOUT)
+                    .await;
+                Err(Error::other("scoped dirty usage acknowledgement deadline elapsed"))
+            }
+        };
+
+        match result {
+            Ok(()) => {
+                let activity = self.scanner_scoped_dirty_usage_activity_confirmation().await?;
+                if activity.instance_id == instance_id {
+                    Ok(activity)
+                } else {
+                    Err(Error::other(
+                        "scoped dirty usage acknowledgement peer restarted before activity confirmation",
+                    ))
+                }
+            }
+            Err(err) => {
+                if Self::is_network_like_error(&err) {
+                    self.prepare_retry_with_timeout(SCANNER_SCOPED_DIRTY_USAGE_STAGE_TIMEOUT)
+                        .await;
+                }
+                match self.scanner_scoped_dirty_usage_activity_confirmation().await {
+                    Ok(activity) if scanner_scoped_dirty_usage_ack_reconciled(&activity, &instance_id) => Ok(activity),
+                    _ => Err(err),
+                }
+            }
+        }
+    }
+
+    async fn scanner_scoped_dirty_usage_activity_confirmation(&self) -> Result<ScannerPeerActivity> {
+        timeout(SCANNER_SCOPED_DIRTY_USAGE_STAGE_TIMEOUT, self.scanner_activity())
+            .await
+            .map_err(|_| Error::other("scoped dirty usage activity confirmation timed out"))?
     }
 
     pub async fn acknowledge_scanner_dirty_usage(&self, instance_id: String, generation: u64) -> Result<ScannerPeerActivity> {
@@ -2845,16 +3027,79 @@ mod tests {
                 rustfs_protos::proto_gen::node_service::ScannerDirtyUsageBucket {
                     bucket: "archive".to_string(),
                     generation: 3,
+                    bucket_incarnation: Uuid::from_u128(0x11111111111111111111111111111111).as_bytes().to_vec().into(),
                 },
                 rustfs_protos::proto_gen::node_service::ScannerDirtyUsageBucket {
                     bucket: "photos".to_string(),
                     generation: 7,
+                    bucket_incarnation: Uuid::from_u128(0x22222222222222222222222222222222).as_bytes().to_vec().into(),
                 },
             ],
             response_proof: b"proof".to_vec().into(),
+            owner_id: "33333333-3333-3333-3333-333333333333".to_string(),
         }
     }
 
+    #[test]
+    fn scanner_scoped_dirty_usage_ack_payloads_split_at_protocol_limit() {
+        use rustfs_protos::scoped_dirty_usage::{SCOPED_DIRTY_USAGE_MAX_ENTRIES, canonical_scoped_dirty_usage_request};
+
+        let entries = (0..=SCOPED_DIRTY_USAGE_MAX_ENTRIES)
+            .map(|index| ScannerScopedDirtyUsageAckEntry {
+                bucket: format!("bucket-{index:02}"),
+                bucket_incarnation: Uuid::from_u128(0x11111111111111111111111111111111),
+                generation: 9,
+            })
+            .collect::<Vec<_>>();
+
+        let payloads = scanner_scoped_dirty_usage_ack_payloads(
+            "33333333-3333-3333-3333-333333333333".to_string(),
+            "0123456789abcdef0123456789abcdef".to_string(),
+            false,
+            entries,
+        )
+        .expect("33 entries should split into valid scoped dirty usage requests");
+
+        assert_eq!(payloads.len(), 2);
+        assert_eq!(payloads[0].entries.len(), SCOPED_DIRTY_USAGE_MAX_ENTRIES as usize);
+        assert_eq!(payloads[1].entries.len(), 1);
+        assert_eq!(payloads[0].entries.first().map(|entry| entry.bucket.as_str()), Some("bucket-00"));
+        assert_eq!(payloads[0].entries.last().map(|entry| entry.bucket.as_str()), Some("bucket-31"));
+        assert_eq!(payloads[1].entries.first().map(|entry| entry.bucket.as_str()), Some("bucket-32"));
+        for payload in payloads {
+            canonical_scoped_dirty_usage_request(&payload).expect("each split scoped ACK payload should be canonical");
+        }
+    }
+
+    #[test]
+    fn scanner_scoped_dirty_usage_ack_reconciliation_requires_same_clean_instance() {
+        let activity = |instance_id: &str, pending| ScannerPeerActivity {
+            instance_id: instance_id.to_string(),
+            namespace_generation: 1,
+            maintenance_generation: 1,
+            protocol_version: SCANNER_ACTIVITY_PROTOCOL_VERSION,
+            topology_digest: Some([1; 32]),
+            data_movement_active: Some(false),
+            dirty_usage_generation: Some(9),
+            dirty_usage_pending: pending,
+            movement_generation: Some(1),
+            publication_blocked: Some(false),
+        };
+
+        assert!(scanner_scoped_dirty_usage_ack_reconciled(
+            &activity("0123456789abcdef0123456789abcdef", Some(false)),
+            "0123456789abcdef0123456789abcdef"
+        ));
+        assert!(!scanner_scoped_dirty_usage_ack_reconciled(
+            &activity("0123456789abcdef0123456789abcdef", Some(true)),
+            "0123456789abcdef0123456789abcdef"
+        ));
+        assert!(!scanner_scoped_dirty_usage_ack_reconciled(
+            &activity("fedcba9876543210fedcba9876543210", Some(false)),
+            "0123456789abcdef0123456789abcdef"
+        ));
+    }
+
     #[test]
     fn scanner_dirty_usage_snapshot_requires_a_complete_authenticated_ordered_view() {
         let decoded = decode_test_scanner_dirty_usage_snapshot(test_scanner_dirty_usage_snapshot_response())
@@ -2863,9 +3108,18 @@ mod tests {
         assert_eq!(decoded.generation, 7);
         assert_eq!(decoded.pending_bucket_count, 2);
         assert_eq!(decoded.protocol_version, SCANNER_DIRTY_USAGE_SNAPSHOT_PROTOCOL_VERSION);
+        assert_eq!(decoded.owner_id, "33333333-3333-3333-3333-333333333333");
         assert!(decoded.complete);
-        assert_eq!(decoded.buckets.get("archive"), Some(&3));
-        assert_eq!(decoded.buckets.get("photos"), Some(&7));
+        assert_eq!(
+            decoded.buckets.get("archive").map(|bucket| bucket.bucket_incarnation),
+            Some(Uuid::from_u128(0x11111111111111111111111111111111))
+        );
+        assert_eq!(decoded.buckets.get("archive").map(|bucket| bucket.generation), Some(3));
+        assert_eq!(
+            decoded.buckets.get("photos").map(|bucket| bucket.bucket_incarnation),
+            Some(Uuid::from_u128(0x22222222222222222222222222222222))
+        );
+        assert_eq!(decoded.buckets.get("photos").map(|bucket| bucket.generation), Some(7));
 
         let overflow_count =
             u64::try_from(SCANNER_DIRTY_USAGE_SNAPSHOT_MAX_ENTRIES + 1).expect("the test snapshot entry limit should fit in u64");
@@ -2916,6 +3170,14 @@ mod tests {
         empty_bucket.buckets[0].bucket.clear();
         cases.push((empty_bucket, "empty bucket name"));
 
+        let mut invalid_owner = test_scanner_dirty_usage_snapshot_response();
+        invalid_owner.owner_id.clear();
+        cases.push((invalid_owner, "snapshot owner"));
+
+        let mut invalid_incarnation = test_scanner_dirty_usage_snapshot_response();
+        invalid_incarnation.buckets[0].bucket_incarnation = Uuid::nil().as_bytes().to_vec().into();
+        cases.push((invalid_incarnation, "bucket incarnation"));
+
         let mut partial = test_scanner_dirty_usage_snapshot_response();
         partial.complete = false;
         cases.push((partial, "entry-limit overflow"));
@@ -2928,6 +3190,7 @@ mod tests {
                 .map(|index| rustfs_protos::proto_gen::node_service::ScannerDirtyUsageBucket {
                     bucket: format!("bucket-{index:04}"),
                     generation: 1,
+                    bucket_incarnation: Uuid::from_u128(0x11111111111111111111111111111111).as_bytes().to_vec().into(),
                 })
                 .collect(),
             ..test_scanner_dirty_usage_snapshot_response()

crates/ecstore/src/services/notification_sys.rs

@@ -14,7 +14,8 @@
 
 use crate::bucket::lifecycle::tier_last_day_stats::DailyAllTierStats;
 use crate::cluster::rpc::{
-    PeerRestClient, ScannerPeerActivity, ScannerPeerDirtyUsageSnapshot, ScannerPublicationLease, TierConfigReloadOutcome,
+    PeerRestClient, ScannerDirtyUsageAcknowledgement, ScannerPeerActivity, ScannerPeerDirtyUsageSnapshot,
+    ScannerPublicationLease, TierConfigReloadOutcome,
 };
 use crate::diagnostics::admin_server_info::get_commit_id;
 use crate::disk::DiskAPI;
@@ -2552,11 +2553,70 @@ impl NotificationSys {
         Ok(snapshots)
     }
 
-    pub async fn acknowledge_scanner_dirty_usage(&self, acknowledgements: Vec<(String, String, u64)>) -> Result<bool> {
+    pub async fn scanner_scoped_dirty_usage_capabilities(
+        &self,
+        acknowledgements: Vec<ScannerDirtyUsageAcknowledgement>,
+    ) -> Result<bool> {
         let mut by_host = HashMap::with_capacity(acknowledgements.len());
-        for (host, instance_id, generation) in acknowledgements {
-            if by_host.insert(host.clone(), (instance_id, generation)).is_some() {
-                return Err(Error::other(format!("duplicate scanner dirty usage acknowledgement target: {host}")));
+        for acknowledgement in acknowledgements {
+            let host = match &acknowledgement {
+                ScannerDirtyUsageAcknowledgement::Scoped { host, .. } => host.clone(),
+                ScannerDirtyUsageAcknowledgement::Generation { .. } => {
+                    return Err(Error::other("scanner scoped dirty usage capability requires scoped acknowledgements"));
+                }
+            };
+            if by_host.insert(host.clone(), acknowledgement).is_some() {
+                return Err(Error::other("duplicate scanner dirty usage acknowledgement target"));
+            }
+        }
+
+        let clients = self
+            .peer_clients
+            .iter()
+            .flatten()
+            .map(|client| (client.grid_host.clone(), client.clone()))
+            .collect::<HashMap<_, _>>();
+        let mut futures = Vec::with_capacity(by_host.len());
+        for (host, acknowledgement) in by_host {
+            let Some(client) = clients.get(&host).cloned() else {
+                return Err(Error::other("scanner scoped dirty usage capability failed: peer is not reachable"));
+            };
+            futures.push(async move {
+                let ScannerDirtyUsageAcknowledgement::Scoped {
+                    owner_id,
+                    instance_id,
+                    entries,
+                    ..
+                } = acknowledgement
+                else {
+                    unreachable!("scoped acknowledgement was validated before probing");
+                };
+                timeout(
+                    SCANNER_ACTIVITY_PROBE_TIMEOUT,
+                    client.scanner_scoped_dirty_usage_capability(owner_id, instance_id, entries),
+                )
+                .await
+                .map_err(|_| Error::other("scanner scoped dirty usage capability timed out"))?
+            });
+        }
+
+        for result in join_all(futures).await {
+            if !result? {
+                return Ok(false);
+            }
+        }
+        Ok(true)
+    }
+
+    pub async fn acknowledge_scanner_dirty_usage(&self, acknowledgements: Vec<ScannerDirtyUsageAcknowledgement>) -> Result<bool> {
+        let mut by_host = HashMap::with_capacity(acknowledgements.len());
+        for acknowledgement in acknowledgements {
+            let host = match &acknowledgement {
+                ScannerDirtyUsageAcknowledgement::Generation { host, .. }
+                | ScannerDirtyUsageAcknowledgement::Scoped { host, .. } => host.clone(),
+            };
+            if by_host.insert(host.clone(), acknowledgement).is_some() {
+                return Err(Error::other("duplicate scanner dirty usage acknowledgement target"));
             }
         }
 
@@ -2568,18 +2628,34 @@ impl NotificationSys {
             .collect::<HashMap<_, _>>();
         let mut failures = Vec::new();
         let mut futures = Vec::with_capacity(by_host.len());
-        for (host, (instance_id, generation)) in by_host {
+        for (host, acknowledgement) in by_host {
             let Some(client) = clients.get(&host).cloned() else {
                 failures.push(format!("peer {host} scanner dirty usage acknowledgement failed: peer is not reachable"));
                 continue;
             };
             futures.push(async move {
-                let result = scanner_activity_with_timeout(
-                    SCANNER_ACTIVITY_PROBE_TIMEOUT,
-                    &host,
-                    client.acknowledge_scanner_dirty_usage(instance_id, generation),
-                )
-                .await;
+                let result = match acknowledgement {
+                    ScannerDirtyUsageAcknowledgement::Generation {
+                        instance_id, generation, ..
+                    } => {
+                        scanner_activity_with_timeout(
+                            SCANNER_ACTIVITY_PROBE_TIMEOUT,
+                            &host,
+                            client.acknowledge_scanner_dirty_usage(instance_id, generation),
+                        )
+                        .await
+                    }
+                    ScannerDirtyUsageAcknowledgement::Scoped {
+                        owner_id,
+                        instance_id,
+                        entries,
+                        ..
+                    } => {
+                        client
+                            .acknowledge_scanner_scoped_dirty_usage(owner_id, instance_id, entries)
+                            .await
+                    }
+                };
                 (host, result)
             });
         }
@@ -4744,15 +4820,28 @@ mod tests {
             peer_topology_hosts: Vec::new(),
         };
         let missing = sys
-            .acknowledge_scanner_dirty_usage(vec![("peer-1".to_string(), "0123456789abcdef0123456789abcdef".to_string(), 7)])
+            .acknowledge_scanner_dirty_usage(vec![ScannerDirtyUsageAcknowledgement::Generation {
+                host: "peer-1".to_string(),
+                instance_id: "0123456789abcdef0123456789abcdef".to_string(),
+                generation: 7,
+            }])
             .await
             .expect_err("a missing acknowledgement target must remain pending");
         assert!(missing.to_string().contains("peer is not reachable"));
 
         let duplicate = sys
             .acknowledge_scanner_dirty_usage(vec![
-                ("peer-1".to_string(), "0123456789abcdef0123456789abcdef".to_string(), 7),
-                ("peer-1".to_string(), "0123456789abcdef0123456789abcdef".to_string(), 7),
+                ScannerDirtyUsageAcknowledgement::Generation {
+                    host: "peer-1".to_string(),
+                    instance_id: "0123456789abcdef0123456789abcdef".to_string(),
+                    generation: 7,
+                },
+                ScannerDirtyUsageAcknowledgement::Scoped {
+                    host: "peer-1".to_string(),
+                    owner_id: "11111111-1111-1111-1111-111111111111".to_string(),
+                    instance_id: "0123456789abcdef0123456789abcdef".to_string(),
+                    entries: Vec::new(),
+                },
             ])
             .await
             .expect_err("duplicate acknowledgement targets must be rejected");

crates/protos/src/generated/proto_gen/node_service.rs

@@ -1257,6 +1257,8 @@ pub struct ScannerDirtyUsageBucket {
     pub bucket: ::prost::alloc::string::String,
     #[prost(uint64, tag = "2")]
     pub generation: u64,
+    #[prost(bytes = "bytes", tag = "3")]
+    pub bucket_incarnation: ::prost::bytes::Bytes,
 }
 #[derive(Clone, PartialEq, Eq, Hash, ::prost::Message)]
 pub struct ScannerDirtyUsageSnapshotRequest {
@@ -1282,6 +1284,8 @@ pub struct ScannerDirtyUsageSnapshotResponse {
     pub buckets: ::prost::alloc::vec::Vec<ScannerDirtyUsageBucket>,
     #[prost(bytes = "bytes", tag = "7")]
     pub response_proof: ::prost::bytes::Bytes,
+    #[prost(string, tag = "8")]
+    pub owner_id: ::prost::alloc::string::String,
 }
 /// Receiver-only protocol. Producers must retain whole-cycle ACK until they
 /// have a durable per-bucket publication proof.

crates/protos/src/lib.rs

@@ -575,11 +575,13 @@ pub fn canonical_scanner_dirty_usage_snapshot_response_body(
     body.push_u64(response.generation);
     body.push_u64(response.pending_bucket_count);
     body.push_u32(response.protocol_version);
+    body.push_str(&response.owner_id)?;
     body.push_bool(response.complete);
     body.push_count(response.buckets.len())?;
     for bucket in &response.buckets {
         body.push_str(&bucket.bucket)?;
         body.push_u64(bucket.generation);
+        body.push_bytes(bucket.bucket_incarnation.as_ref())?;
     }
     Ok(body.finish())
 }
@@ -1842,13 +1844,16 @@ mod scanner_activity_tests {
                 ScannerDirtyUsageBucket {
                     bucket: "archive".to_string(),
                     generation: 3,
+                    bucket_incarnation: vec![1; 16].into(),
                 },
                 ScannerDirtyUsageBucket {
                     bucket: "photos".to_string(),
                     generation: 7,
+                    bucket_incarnation: vec![2; 16].into(),
                 },
             ],
             response_proof: vec![9; 32].into(),
+            owner_id: "11111111-1111-1111-1111-111111111111".to_string(),
         };
         let baseline = canonical_scanner_dirty_usage_snapshot_response_body(&[1; 16], &response)
             .expect("scanner dirty usage snapshot response should encode");
@@ -1865,6 +1870,9 @@ mod scanner_activity_tests {
         let mut protocol = response.clone();
         protocol.protocol_version = 2;
         variants.push(protocol);
+        let mut owner = response.clone();
+        owner.owner_id = "22222222-2222-2222-2222-222222222222".to_string();
+        variants.push(owner);
         let mut complete = response.clone();
         complete.complete = false;
         variants.push(complete);
@@ -1874,6 +1882,9 @@ mod scanner_activity_tests {
         let mut bucket_generation = response.clone();
         bucket_generation.buckets[0].generation = 4;
         variants.push(bucket_generation);
+        let mut bucket_incarnation = response.clone();
+        bucket_incarnation.buckets[0].bucket_incarnation = vec![3; 16].into();
+        variants.push(bucket_incarnation);
         let mut bucket_order = response.clone();
         bucket_order.buckets.reverse();
         variants.push(bucket_order);

crates/protos/src/node.proto

@@ -885,6 +885,7 @@ message ScannerActivityResponse {
 message ScannerDirtyUsageBucket {
   string bucket = 1;
   uint64 generation = 2;
+  bytes bucket_incarnation = 3;
 }
 
 message ScannerDirtyUsageSnapshotRequest {
@@ -901,6 +902,7 @@ message ScannerDirtyUsageSnapshotResponse {
   bool complete = 5;
   repeated ScannerDirtyUsageBucket buckets = 6;
   bytes response_proof = 7;
+  string owner_id = 8;
 }
 
 // Receiver-only protocol. Producers must retain whole-cycle ACK until they

crates/scanner/src/lib.rs

@@ -100,6 +100,7 @@ pub use storage_api::ScannerReplicationConfig as ReplicationConfig;
 pub use storage_api::scan::{
     SCANNER_ACTIVITY_PROTOCOL_VERSION, SCANNER_ACTIVITY_V6_PROTOCOL_VERSION, SCANNER_DIRTY_USAGE_SNAPSHOT_MAX_ENTRIES,
     SCANNER_DIRTY_USAGE_SNAPSHOT_PROTOCOL_VERSION, SCANNER_DIRTY_USAGE_SNAPSHOT_RPC_MAX_MESSAGE_SIZE,
+    SCANNER_SCOPED_DIRTY_USAGE_ACK_MAX_ENTRIES,
 };
 pub use workload_admission::set_scanner_workload_admission_snapshot_provider;
 

crates/scanner/src/scanner.rs

@@ -2216,10 +2216,7 @@ where
         false
     } else if let Some(notification_system) = storeapi.scanner_notification_system() {
         let acknowledgement_count = remote_dirty_usage_acknowledgements.len();
-        let acknowledgements = remote_dirty_usage_acknowledgements
-            .into_iter()
-            .map(|acknowledgement| (acknowledgement.host, acknowledgement.instance_id, acknowledgement.generation))
-            .collect();
+        let acknowledgements = remote_dirty_usage_acknowledgements.into_iter().map(Into::into).collect();
         remote_dirty_usage_acknowledgement_pending(
             cycle_info.current,
             acknowledgement_count,
@@ -3578,9 +3575,10 @@ use usage_store::*;
 
 pub use activity::scanner_topology_digest;
 pub(crate) use activity::{
-    ScannerActivitySnapshot, ScannerDirtyUsageAcknowledgement, probe_scanner_activity, scanner_activity_allows_usage_publication,
-    scanner_activity_dirty_usage_state_for_host, scanner_activity_publication_lease_targets, scanner_activity_snapshot_digest,
-    scanner_activity_structural_digest, scanner_dirty_usage_acknowledgements,
+    ScannerActivitySnapshot, ScannerDirtyUsageAcknowledgement, ScannerDirtyUsageAcknowledgementKind, probe_scanner_activity,
+    scanner_activity_allows_usage_publication, scanner_activity_dirty_usage_state_for_host,
+    scanner_activity_publication_lease_targets, scanner_activity_snapshot_digest, scanner_activity_structural_digest,
+    scanner_dirty_usage_acknowledgements,
 };
 pub(crate) use activity::{ScannerCycleOutcome, scanner_cycle_outcome_with_pending_maintenance};
 pub use backlog::{

crates/scanner/src/scanner/activity.rs

@@ -445,7 +445,34 @@ pub(crate) type ScannerActivitySnapshot = BTreeMap<String, ScannerNodeActivity>;
 pub(crate) struct ScannerDirtyUsageAcknowledgement {
     pub(crate) host: String,
     pub(crate) instance_id: String,
-    pub(crate) generation: u64,
+    pub(crate) kind: ScannerDirtyUsageAcknowledgementKind,
+}
+
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub(crate) enum ScannerDirtyUsageAcknowledgementKind {
+    Generation(u64),
+    Scoped {
+        owner_id: String,
+        entries: Vec<crate::storage_api::EcstoreScannerScopedDirtyUsageAckEntry>,
+    },
+}
+
+impl From<ScannerDirtyUsageAcknowledgement> for crate::storage_api::EcstoreScannerDirtyUsageAcknowledgement {
+    fn from(acknowledgement: ScannerDirtyUsageAcknowledgement) -> Self {
+        match acknowledgement.kind {
+            ScannerDirtyUsageAcknowledgementKind::Generation(generation) => Self::Generation {
+                host: acknowledgement.host,
+                instance_id: acknowledgement.instance_id,
+                generation,
+            },
+            ScannerDirtyUsageAcknowledgementKind::Scoped { owner_id, entries } => Self::Scoped {
+                host: acknowledgement.host,
+                owner_id,
+                instance_id: acknowledgement.instance_id,
+                entries,
+            },
+        }
+    }
 }
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
@@ -974,7 +1001,7 @@ pub(crate) fn scanner_dirty_usage_acknowledgements(snapshot: &ScannerActivitySna
         .map(|(host, activity)| ScannerDirtyUsageAcknowledgement {
             host: host.clone(),
             instance_id: activity.instance_id.clone(),
-            generation: activity.dirty_usage_generation,
+            kind: ScannerDirtyUsageAcknowledgementKind::Generation(activity.dirty_usage_generation),
         })
         .collect()
 }

crates/scanner/src/scanner/tests.rs

@@ -7433,7 +7433,7 @@ fn finalizing_a_saved_enum_without_proof_keeps_dirty_pending() {
     let remote_acknowledgement = ScannerDirtyUsageAcknowledgement {
         host: "node-2".to_string(),
         instance_id: "0123456789abcdef0123456789abcdef".to_string(),
-        generation: 11,
+        kind: ScannerDirtyUsageAcknowledgementKind::Generation(11),
     };
     let unsaved = crate::scanner_io::ScannerCycleResult::new(ScannerCycleStatus::Complete, Some(dirty_snapshot.clone()))
         .with_remote_dirty_usage_acknowledgements(vec![remote_acknowledgement.clone()]);
@@ -8982,7 +8982,7 @@ fn post_lease_activity_proof_rejects_a_put_tail_that_finished_before_lease_acqui
         ScannerDirtyUsageAcknowledgement {
             host: "node-2".to_string(),
             instance_id: "epoch-a".to_string(),
-            generation: 5,
+            kind: ScannerDirtyUsageAcknowledgementKind::Generation(5),
         },
     ]);
     let (outcome, _, acknowledgements) = finalize_scanner_cycle_result(
@@ -9142,7 +9142,7 @@ fn scanner_dirty_usage_acknowledgements_exclude_local_and_clean_nodes() {
         vec![ScannerDirtyUsageAcknowledgement {
             host: "node-3".to_string(),
             instance_id: "epoch-dirty".to_string(),
-            generation: 11,
+            kind: ScannerDirtyUsageAcknowledgementKind::Generation(11),
         }]
     );
 }

crates/scanner/src/scanner/tests/scoped_ack_publication.rs

@@ -463,7 +463,7 @@ async fn scoped_ack_publication_rejects_builder_mutation_after_real_root_publish
             "remote_ack_target" => scan.with_remote_dirty_usage_acknowledgements(vec![ScannerDirtyUsageAcknowledgement {
                 host: "proof-peer:9000".to_string(),
                 instance_id: crate::scanner_activity_epoch().to_string(),
-                generation: changed_generation,
+                kind: crate::scanner::ScannerDirtyUsageAcknowledgementKind::Generation(changed_generation),
             }]),
             "publication_epoch" => scan.with_publication_epoch(Some(changed_epoch)),
             "remote_lease_targets" => scan.with_remote_publication_lease_targets(vec![(

crates/scanner/src/scanner_io.rs

@@ -148,19 +148,26 @@ struct ScannerPeerDirtyUsageExpectation {
     pending: bool,
 }
 
-fn verified_remote_dirty_usage_buckets(
+#[derive(Debug, PartialEq, Eq)]
+struct VerifiedRemoteDirtyUsage {
+    dirty_buckets: HashSet<String>,
+    acknowledgements: Vec<crate::scanner::ScannerDirtyUsageAcknowledgement>,
+}
+
+fn verified_remote_dirty_usage(
     expected_peers: &HashMap<String, ScannerPeerDirtyUsageExpectation>,
     peer_snapshots: Vec<(String, EcstoreScannerPeerDirtyUsageSnapshot)>,
-) -> Option<HashSet<String>> {
+) -> Option<VerifiedRemoteDirtyUsage> {
     if expected_peers.is_empty() || peer_snapshots.len() != expected_peers.len() {
         return None;
     }
 
     let mut received_peers = HashSet::with_capacity(peer_snapshots.len());
     let mut dirty_buckets = HashSet::new();
+    let mut acknowledgements = Vec::new();
     for (host, snapshot) in peer_snapshots {
         let expected = expected_peers.get(&host)?;
-        if !received_peers.insert(host)
+        if !received_peers.insert(host.clone())
             || snapshot.instance_id != expected.instance_id
             || snapshot.generation != expected.generation
             || snapshot.generation == u64::MAX
@@ -171,10 +178,44 @@ fn verified_remote_dirty_usage_buckets(
         {
             return None;
         }
-        dirty_buckets.extend(snapshot.buckets.into_keys());
+        let entries = snapshot
+            .buckets
+            .iter()
+            .map(|(bucket, state)| crate::storage_api::EcstoreScannerScopedDirtyUsageAckEntry {
+                bucket: bucket.clone(),
+                bucket_incarnation: state.bucket_incarnation,
+                generation: state.generation,
+            })
+            .collect::<Vec<_>>();
+        dirty_buckets.extend(snapshot.buckets.keys().cloned());
+        if !entries.is_empty() {
+            acknowledgements.push(crate::scanner::ScannerDirtyUsageAcknowledgement {
+                host,
+                instance_id: snapshot.instance_id,
+                kind: crate::scanner::ScannerDirtyUsageAcknowledgementKind::Scoped {
+                    owner_id: snapshot.owner_id,
+                    entries,
+                },
+            });
+        }
     }
 
-    (received_peers.len() == expected_peers.len()).then_some(dirty_buckets)
+    (received_peers.len() == expected_peers.len()).then_some(VerifiedRemoteDirtyUsage {
+        dirty_buckets,
+        acknowledgements,
+    })
+}
+
+fn scanner_scoped_dirty_usage_ack_exceeds_cost_threshold(
+    acknowledgements: &[crate::scanner::ScannerDirtyUsageAcknowledgement],
+) -> bool {
+    acknowledgements.iter().any(|acknowledgement| {
+        matches!(
+            &acknowledgement.kind,
+            crate::scanner::ScannerDirtyUsageAcknowledgementKind::Scoped { entries, .. }
+                if entries.len() > crate::SCANNER_SCOPED_DIRTY_USAGE_ACK_MAX_ENTRIES
+        )
+    })
 }
 
 fn complete_scanner_cache_snapshot_plan_digest(

crates/scanner/src/scanner_io/io_cycle.rs

@@ -107,23 +107,32 @@ struct ScannerBucketScopeResolution<'a> {
     requires_full_scan: bool,
 }
 
+struct ScannerBucketScopeResolutionResult {
+    scope: ScannerBucketScanScope,
+    remote_dirty_usage_acknowledgements: Vec<crate::scanner::ScannerDirtyUsageAcknowledgement>,
+}
+
 async fn resolve_scanner_bucket_scan_scope<S>(
     store: &S,
     distributed: bool,
     resolution: ScannerBucketScopeResolution<'_>,
-) -> ScannerBucketScanScope
+) -> ScannerBucketScopeResolutionResult
 where
     S: ScannerStorage,
 {
+    let default_result = |scope: ScannerBucketScanScope| ScannerBucketScopeResolutionResult {
+        scope,
+        remote_dirty_usage_acknowledgements: Vec::new(),
+    };
     if resolution.requires_full_scan {
-        return ScannerBucketScanScope::default();
+        return default_result(ScannerBucketScanScope::default());
     }
     if !resolution.requested_scope.is_default()
         || !resolution.dirty_usage_snapshot.covers_all_pending
         || resolution.dirty_usage_snapshot.generation == u64::MAX
         || resolution.dirty_usage_snapshot.buckets.len() > crate::SCANNER_DIRTY_USAGE_SNAPSHOT_MAX_ENTRIES
     {
-        return resolution.requested_scope;
+        return default_result(resolution.requested_scope);
     }
 
     let mut dirty_buckets = resolution
@@ -134,10 +143,10 @@ where
         .collect::<HashSet<_>>();
     if distributed {
         let Some(notification_system) = store.scanner_notification_system() else {
-            return resolution.requested_scope;
+            return default_result(resolution.requested_scope);
         };
         let Ok(peer_snapshots) = notification_system.scanner_dirty_usage_snapshots().await else {
-            return resolution.requested_scope;
+            return default_result(resolution.requested_scope);
         };
         let mut expected_peers = HashMap::new();
         for (host, lease_instance_id, _) in crate::scanner::scanner_activity_publication_lease_targets(resolution.activity_before)
@@ -145,10 +154,10 @@ where
             let Some((activity_instance_id, generation, pending)) =
                 crate::scanner::scanner_activity_dirty_usage_state_for_host(resolution.activity_before, &host)
             else {
-                return resolution.requested_scope;
+                return default_result(resolution.requested_scope);
             };
             if activity_instance_id != lease_instance_id || expected_peers.contains_key(&host) {
-                return resolution.requested_scope;
+                return default_result(resolution.requested_scope);
             }
             expected_peers.insert(
                 host,
@@ -159,19 +168,76 @@ where
                 },
             );
         }
-        let Some(remote_dirty_buckets) = verified_remote_dirty_usage_buckets(&expected_peers, peer_snapshots) else {
-            return resolution.requested_scope;
+        let Some(remote_dirty_usage) = verified_remote_dirty_usage(&expected_peers, peer_snapshots) else {
+            return default_result(resolution.requested_scope);
+        };
+        dirty_buckets.extend(remote_dirty_usage.dirty_buckets);
+        let scope = scoped_scan_scope_from_dirty_buckets(
+            resolution.requested_scope,
+            dirty_buckets,
+            true,
+            resolution.all_buckets,
+            resolution.baseline_proof,
+        );
+        if scope.is_default() {
+            return default_result(scope);
+        }
+        let Some(selected_buckets) = scope.selected_buckets.as_ref() else {
+            return default_result(scope);
+        };
+        let mut scoped_acknowledgements = Vec::with_capacity(remote_dirty_usage.acknowledgements.len());
+        for acknowledgement in remote_dirty_usage.acknowledgements {
+            let crate::scanner::ScannerDirtyUsageAcknowledgement {
+                host,
+                instance_id,
+                kind: crate::scanner::ScannerDirtyUsageAcknowledgementKind::Scoped { owner_id, entries },
+            } = acknowledgement
+            else {
+                return default_result(scope);
+            };
+            let entries = entries
+                .into_iter()
+                .filter(|entry| selected_buckets.contains(&entry.bucket))
+                .collect::<Vec<_>>();
+            if !entries.is_empty() {
+                scoped_acknowledgements.push(crate::scanner::ScannerDirtyUsageAcknowledgement {
+                    host,
+                    instance_id,
+                    kind: crate::scanner::ScannerDirtyUsageAcknowledgementKind::Scoped { owner_id, entries },
+                });
+            }
+        }
+        if super::scanner_scoped_dirty_usage_ack_exceeds_cost_threshold(&scoped_acknowledgements) {
+            return default_result(ScannerBucketScanScope::default());
+        }
+        if !scoped_acknowledgements.is_empty() {
+            let capability_acknowledgements = scoped_acknowledgements
+                .clone()
+                .into_iter()
+                .map(Into::into)
+                .collect::<Vec<crate::storage_api::EcstoreScannerDirtyUsageAcknowledgement>>();
+            if !matches!(
+                notification_system
+                    .scanner_scoped_dirty_usage_capabilities(capability_acknowledgements)
+                    .await,
+                Ok(true)
+            ) {
+                return default_result(ScannerBucketScanScope::default());
+            }
+        }
+        return ScannerBucketScopeResolutionResult {
+            scope,
+            remote_dirty_usage_acknowledgements: scoped_acknowledgements,
         };
-        dirty_buckets.extend(remote_dirty_buckets);
     }
 
-    scoped_scan_scope_from_dirty_buckets(
+    default_result(scoped_scan_scope_from_dirty_buckets(
         resolution.requested_scope,
         dirty_buckets,
         true,
         resolution.all_buckets,
         resolution.baseline_proof,
-    )
+    ))
 }
 
 pub(crate) async fn nsscanner_with_storage_status_scoped<S>(store: &S, request: ScannerCycleRequest) -> Result<ScannerCycleResult>
@@ -294,7 +360,7 @@ where
     let bucket_coverage_digest = scanner_bucket_plan_digest(&all_buckets, activity_digest);
     let execution_digest = scanner_bucket_work_digest(bucket_coverage_digest, scan_mode, requires_full_scan);
     let dirty_usage_snapshot = Arc::new(snapshot_dirty_usage_buckets(&all_buckets, dirty_generation_before_bucket_list));
-    let scan_scope = resolve_scanner_bucket_scan_scope(
+    let scope_resolution = resolve_scanner_bucket_scan_scope(
         store,
         distributed,
         ScannerBucketScopeResolution {
@@ -314,6 +380,8 @@ where
         },
     )
     .await;
+    let remote_dirty_usage_acknowledgements = scope_resolution.remote_dirty_usage_acknowledgements;
+    let scan_scope = scope_resolution.scope;
     #[cfg(test)]
     if let Some(observer) = resolved_scope_observer {
         let _ = observer.send(scan_scope.clone());
@@ -674,11 +742,14 @@ where
     if cycle_status == ScannerCycleStatus::Complete {
         complete_tier_registry_cycle(want_cycle, leader_epoch);
     }
-    let remote_dirty_usage_acknowledgements = if cycle_status == ScannerCycleStatus::Complete {
-        crate::scanner::scanner_dirty_usage_acknowledgements(&activity_before)
-    } else {
-        Vec::new()
-    };
+    let remote_dirty_usage_acknowledgements =
+        if cycle_status == ScannerCycleStatus::Complete && !remote_dirty_usage_acknowledgements.is_empty() {
+            remote_dirty_usage_acknowledgements
+        } else if cycle_status == ScannerCycleStatus::Complete && scan_scope.is_default() {
+            crate::scanner::scanner_dirty_usage_acknowledgements(&activity_before)
+        } else {
+            Vec::new()
+        };
     Ok(ScannerCycleResult::new(cycle_status, dirty_usage_clear)
         .with_publication_epoch(publication_epoch)
         .with_activity_digest(activity_digest)

crates/scanner/src/scanner_io/tests.rs

@@ -1561,6 +1561,7 @@ fn peer_dirty_usage_snapshot(
     buckets: &[(&str, u64)],
 ) -> EcstoreScannerPeerDirtyUsageSnapshot {
     EcstoreScannerPeerDirtyUsageSnapshot {
+        owner_id: uuid::Uuid::from_u128(0x11111111111111111111111111111111).to_string(),
         instance_id: instance_id.to_string(),
         generation,
         pending_bucket_count: u64::try_from(buckets.len()).expect("test bucket count should fit"),
@@ -1568,7 +1569,15 @@ fn peer_dirty_usage_snapshot(
         complete,
         buckets: buckets
             .iter()
-            .map(|(bucket, generation)| ((*bucket).to_string(), *generation))
+            .map(|(bucket, generation)| {
+                (
+                    (*bucket).to_string(),
+                    crate::storage_api::EcstoreScannerPeerDirtyUsageBucket {
+                        bucket_incarnation: uuid::Uuid::from_u128(0x22222222222222222222222222222222),
+                        generation: *generation,
+                    },
+                )
+            })
             .collect(),
     }
 }
@@ -1595,7 +1604,7 @@ fn verified_remote_dirty_usage_buckets_merges_only_complete_current_snapshots()
     ]);
 
     assert_eq!(
-        verified_remote_dirty_usage_buckets(
+        verified_remote_dirty_usage(
             &expected_peers,
             vec![
                 (
@@ -1608,10 +1617,63 @@ fn verified_remote_dirty_usage_buckets_merges_only_complete_current_snapshots()
                 ),
             ],
         ),
-        Some(HashSet::from(["photos".to_string(), "archive".to_string()]))
+        Some(VerifiedRemoteDirtyUsage {
+            dirty_buckets: HashSet::from(["photos".to_string(), "archive".to_string()]),
+            acknowledgements: vec![
+                crate::scanner::ScannerDirtyUsageAcknowledgement {
+                    host: "node-a:9000".to_string(),
+                    instance_id: "instance-a".to_string(),
+                    kind: crate::scanner::ScannerDirtyUsageAcknowledgementKind::Scoped {
+                        owner_id: uuid::Uuid::from_u128(0x11111111111111111111111111111111).to_string(),
+                        entries: vec![crate::storage_api::EcstoreScannerScopedDirtyUsageAckEntry {
+                            bucket: "photos".to_string(),
+                            bucket_incarnation: uuid::Uuid::from_u128(0x22222222222222222222222222222222),
+                            generation: 7,
+                        }],
+                    },
+                },
+                crate::scanner::ScannerDirtyUsageAcknowledgement {
+                    host: "node-b:9000".to_string(),
+                    instance_id: "instance-b".to_string(),
+                    kind: crate::scanner::ScannerDirtyUsageAcknowledgementKind::Scoped {
+                        owner_id: uuid::Uuid::from_u128(0x11111111111111111111111111111111).to_string(),
+                        entries: vec![crate::storage_api::EcstoreScannerScopedDirtyUsageAckEntry {
+                            bucket: "archive".to_string(),
+                            bucket_incarnation: uuid::Uuid::from_u128(0x22222222222222222222222222222222),
+                            generation: 3,
+                        }],
+                    },
+                },
+            ],
+        })
     );
 }
 
+#[test]
+fn scanner_scoped_dirty_usage_ack_cost_threshold_is_single_protocol_batch() {
+    let acknowledgement = |entry_count: usize| crate::scanner::ScannerDirtyUsageAcknowledgement {
+        host: "node-a:9000".to_string(),
+        instance_id: "instance-a".to_string(),
+        kind: crate::scanner::ScannerDirtyUsageAcknowledgementKind::Scoped {
+            owner_id: uuid::Uuid::from_u128(0x11111111111111111111111111111111).to_string(),
+            entries: (0..entry_count)
+                .map(|index| crate::storage_api::EcstoreScannerScopedDirtyUsageAckEntry {
+                    bucket: format!("bucket-{index:02}"),
+                    bucket_incarnation: uuid::Uuid::from_u128(0x22222222222222222222222222222222),
+                    generation: 7,
+                })
+                .collect(),
+        },
+    };
+
+    assert!(!scanner_scoped_dirty_usage_ack_exceeds_cost_threshold(&[acknowledgement(
+        crate::SCANNER_SCOPED_DIRTY_USAGE_ACK_MAX_ENTRIES
+    )]));
+    assert!(scanner_scoped_dirty_usage_ack_exceeds_cost_threshold(&[acknowledgement(
+        crate::SCANNER_SCOPED_DIRTY_USAGE_ACK_MAX_ENTRIES + 1
+    )]));
+}
+
 #[test]
 fn verified_remote_dirty_usage_buckets_rejects_incomplete_or_stale_peer_state() {
     let expected_peers = HashMap::from([(
@@ -1630,7 +1692,7 @@ fn verified_remote_dirty_usage_buckets_rejects_incomplete_or_stale_peer_state()
         peer_dirty_usage_snapshot("instance-a", 7, true, &[]),
     ] {
         assert!(
-            verified_remote_dirty_usage_buckets(&expected_peers, vec![("node-a:9000".to_string(), snapshot)]).is_none(),
+            verified_remote_dirty_usage(&expected_peers, vec![("node-a:9000".to_string(), snapshot)]).is_none(),
             "incomplete, stale, mismatched, or empty pending peer state must fall back to a full scan"
         );
     }

crates/scanner/src/storage_api.rs

@@ -103,8 +103,13 @@ pub(crate) use rustfs_ecstore::api::rebalance::{
     RebalStatus as EcstoreRebalStatus, RebalanceInfo as EcstoreRebalanceInfo, RebalanceMeta as EcstoreRebalanceMeta,
     RebalanceStats as EcstoreRebalanceStats,
 };
+#[cfg(test)]
+pub(crate) use rustfs_ecstore::api::rpc::ScannerPeerDirtyUsageBucket as EcstoreScannerPeerDirtyUsageBucket;
 pub(crate) use rustfs_ecstore::api::rpc::{
-    ScannerBucketListing as EcstoreScannerBucketListing, ScannerPeerDirtyUsageSnapshot as EcstoreScannerPeerDirtyUsageSnapshot,
+    ScannerBucketListing as EcstoreScannerBucketListing,
+    ScannerDirtyUsageAcknowledgement as EcstoreScannerDirtyUsageAcknowledgement,
+    ScannerPeerDirtyUsageSnapshot as EcstoreScannerPeerDirtyUsageSnapshot,
+    ScannerScopedDirtyUsageAckEntry as EcstoreScannerScopedDirtyUsageAckEntry,
 };
 #[cfg(test)]
 pub(crate) use rustfs_ecstore::api::runtime::InstanceContext as EcstoreInstanceContext;
@@ -315,6 +320,7 @@ pub(crate) mod scan {
     pub use super::storage_contracts::{
         SCANNER_ACTIVITY_PROTOCOL_VERSION, SCANNER_ACTIVITY_V6_PROTOCOL_VERSION, SCANNER_DIRTY_USAGE_SNAPSHOT_MAX_ENTRIES,
         SCANNER_DIRTY_USAGE_SNAPSHOT_PROTOCOL_VERSION, SCANNER_DIRTY_USAGE_SNAPSHOT_RPC_MAX_MESSAGE_SIZE,
+        SCANNER_SCOPED_DIRTY_USAGE_ACK_MAX_ENTRIES,
     };
 }
 

crates/storage-api/src/lib.rs

@@ -56,8 +56,9 @@ pub const SCANNER_ACTIVITY_PREVIOUS_PROTOCOL_VERSION: u32 = 5;
 /// state is not authenticated by that version.
 pub const SCANNER_ACTIVITY_V6_PROTOCOL_VERSION: u32 = 6;
 pub const SCANNER_ACTIVITY_PROTOCOL_VERSION: u32 = 7;
-pub const SCANNER_DIRTY_USAGE_SNAPSHOT_PROTOCOL_VERSION: u32 = 1;
-pub const SCANNER_DIRTY_USAGE_SNAPSHOT_MAX_ENTRIES: usize = 4096;
+pub const SCANNER_DIRTY_USAGE_SNAPSHOT_PROTOCOL_VERSION: u32 = 2;
+pub const SCANNER_SCOPED_DIRTY_USAGE_ACK_MAX_ENTRIES: usize = 32;
+pub const SCANNER_DIRTY_USAGE_SNAPSHOT_MAX_ENTRIES: usize = SCANNER_SCOPED_DIRTY_USAGE_ACK_MAX_ENTRIES;
 pub const SCANNER_DIRTY_USAGE_SNAPSHOT_RPC_MAX_MESSAGE_SIZE: usize = 512 * 1024;
 
 #[derive(Debug, serde::Deserialize, serde::Serialize)]

rustfs/src/server/http.rs

@@ -2418,6 +2418,7 @@ fn get_default_tcp_keepalive() -> TcpKeepalive {
 mod tests {
     use super::*;
     use crate::server::compress::RequestPathCategory;
+    use crate::storage_api::server::http::ScannerScopedDirtyUsageAckEntry;
     use bytes::Bytes;
     use http::Request as HttpRequest;
     use http::{HeaderMap, StatusCode};
@@ -3454,9 +3455,9 @@ mod tests {
             .scanner_scoped_dirty_usage_capability(
                 "11111111-1111-1111-1111-111111111111".to_string(),
                 "a".repeat(32),
-                vec![rustfs_protos::proto_gen::node_service::ScannerScopedDirtyUsageEntry {
-                    bucket: "photos".into(),
-                    bucket_incarnation: vec![1; 16].into(),
+                vec![ScannerScopedDirtyUsageAckEntry {
+                    bucket: "photos".to_string(),
+                    bucket_incarnation: uuid::Uuid::from_u128(0x11111111111111111111111111111111),
                     generation: 8,
                 }],
             )

rustfs/src/storage/rpc/node_service.rs

@@ -303,25 +303,38 @@ fn scanner_activity_response(
     }
 }
 
-fn scanner_dirty_usage_snapshot_response(
+async fn scanner_dirty_usage_snapshot_response(
+    store: &ECStore,
     snapshot: rustfs_scanner::ScannerDirtyUsageSnapshot,
-) -> ScannerDirtyUsageSnapshotResponse {
-    ScannerDirtyUsageSnapshotResponse {
+) -> Result<ScannerDirtyUsageSnapshotResponse, Status> {
+    if store.id.is_nil() {
+        return Err(Status::failed_precondition("scanner dirty usage snapshot owner is unavailable"));
+    }
+    let mut buckets = Vec::with_capacity(snapshot.buckets.len());
+    for bucket in snapshot.buckets {
+        let bucket_incarnation = store
+            .bucket_incarnation_id_from_disk(&bucket.bucket)
+            .await
+            .map_err(|_| Status::failed_precondition("scanner dirty usage bucket incarnation is unavailable"))?;
+        if bucket_incarnation.is_nil() {
+            return Err(Status::failed_precondition("scanner dirty usage bucket incarnation is unavailable"));
+        }
+        buckets.push(ScannerDirtyUsageBucket {
+            bucket: bucket.bucket,
+            generation: bucket.generation,
+            bucket_incarnation: bucket_incarnation.as_bytes().to_vec().into(),
+        });
+    }
+    Ok(ScannerDirtyUsageSnapshotResponse {
         instance_id: rustfs_scanner::scanner_activity_epoch().to_string(),
         generation: snapshot.generation,
         pending_bucket_count: snapshot.pending_bucket_count,
         protocol_version: rustfs_scanner::SCANNER_DIRTY_USAGE_SNAPSHOT_PROTOCOL_VERSION,
         complete: snapshot.complete,
-        buckets: snapshot
-            .buckets
-            .into_iter()
-            .map(|bucket| ScannerDirtyUsageBucket {
-                bucket: bucket.bucket,
-                generation: bucket.generation,
-            })
-            .collect(),
+        buckets,
         response_proof: Bytes::new(),
-    }
+        owner_id: store.id.to_string(),
+    })
 }
 
 fn scanner_activity_response_v7(
@@ -2219,11 +2232,14 @@ impl Node for NodeService {
             .as_ref()
             .try_into()
             .map_err(|_| Status::invalid_argument("scanner dirty usage snapshot challenge must be 16 bytes"))?;
-        let snapshot = rustfs_scanner::scanner_dirty_usage_snapshot(rustfs_scanner::SCANNER_DIRTY_USAGE_SNAPSHOT_MAX_ENTRIES);
+        let store = self
+            .resolve_object_store()
+            .ok_or_else(|| Status::unavailable("storage layer is not initialized"))?;
+        let snapshot = rustfs_scanner::scanner_dirty_usage_snapshot(rustfs_scanner::SCANNER_SCOPED_DIRTY_USAGE_ACK_MAX_ENTRIES);
         if snapshot.generation == u64::MAX {
             return Err(Status::resource_exhausted("scanner dirty usage generation is exhausted"));
         }
-        let mut response = scanner_dirty_usage_snapshot_response(snapshot);
+        let mut response = scanner_dirty_usage_snapshot_response(&store, snapshot).await?;
         let canonical = rustfs_protos::canonical_scanner_dirty_usage_snapshot_response_body(&challenge, &response)
             .map_err(|_| Status::internal("scanner dirty usage snapshot response is too large to authenticate"))?;
         response.response_proof = sign_tonic_rpc_response_proof(&canonical)
@@ -6510,7 +6526,28 @@ mod tests {
     #[tokio::test]
     async fn test_scanner_dirty_usage_snapshot_requires_body_bound_auth_and_signs_a_consistent_view() {
         let _ = rustfs_credentials::set_global_rpc_secret("scanner-dirty-usage-snapshot-test-secret".to_string());
-        let service = create_test_node_service();
+        let _ = rustfs_credentials::init_global_action_credentials(
+            Some("TESTROOTACCESSKEY".to_string()),
+            Some("TESTROOTSECRET123".to_string()),
+        );
+        let temp_dir = tempfile::tempdir().expect("scanner dirty usage snapshot RPC test directory");
+        let env = rustfs_test_utils::TestECStoreEnv::builder()
+            .base_dir(temp_dir.path())
+            .build()
+            .await;
+        ObjectStore::new(Arc::clone(&env.ecstore))
+            .save_iam_config(serde_json::json!({"version": 1}), format!("{}/format.json", *IAM_CONFIG_PREFIX))
+            .await
+            .expect("seed IAM format");
+        let iam = rustfs_iam::build_iam_sys(Arc::clone(&env.ecstore))
+            .await
+            .expect("build isolated IAM");
+        let context = Arc::new(crate::runtime_sources::AppContext::with_default_interfaces(
+            Arc::clone(&env.ecstore),
+            iam,
+            Arc::new(KmsServiceManager::new()),
+        ));
+        let service = make_server_for_context(Some(context));
         let unsigned = service
             .scanner_dirty_usage_snapshot(Request::new(ScannerDirtyUsageSnapshotRequest {
                 challenge: vec![7; 16].into(),
@@ -6564,6 +6601,7 @@ mod tests {
             .into_inner();
         assert_eq!(response.instance_id, rustfs_scanner::scanner_activity_epoch());
         assert_eq!(response.protocol_version, rustfs_scanner::SCANNER_DIRTY_USAGE_SNAPSHOT_PROTOCOL_VERSION);
+        assert!(Uuid::parse_str(&response.owner_id).is_ok_and(|owner_id| !owner_id.is_nil()));
         let bucket_count = u64::try_from(response.buckets.len()).expect("snapshot bucket count should fit in u64");
         assert_eq!(response.complete, response.pending_bucket_count == bucket_count);
         let canonical = rustfs_protos::canonical_scanner_dirty_usage_snapshot_response_body(&challenge, &response)

rustfs/src/storage/storage_api.rs

@@ -550,8 +550,8 @@ pub(crate) mod ecstore_rpc {
     };
     #[cfg(test)]
     pub(crate) use rustfs_ecstore::api::rpc::{
-        build_put_file_auth_trailer, gen_signature_headers, gen_tonic_signature_headers, set_tonic_canonical_body_digest,
-        verify_put_file_capability, verify_tonic_rpc_response_proof,
+        ScannerScopedDirtyUsageAckEntry, build_put_file_auth_trailer, gen_signature_headers, gen_tonic_signature_headers,
+        set_tonic_canonical_body_digest, verify_put_file_capability, verify_tonic_rpc_response_proof,
     };
 }
 
@@ -694,6 +694,8 @@ pub(crate) type ServerContextSlot = crate::storage::runtime_sources::ServerConte
 pub(crate) type LocalPeerS3Client = ecstore_rpc::LocalPeerS3Client;
 #[cfg(test)]
 pub(crate) type PeerRestClient = ecstore_rpc::PeerRestClient;
+#[cfg(test)]
+pub(crate) type ScannerScopedDirtyUsageAckEntry = ecstore_rpc::ScannerScopedDirtyUsageAckEntry;
 pub(crate) type MetricType = ecstore_metrics::MetricType;
 pub(crate) type ObjectPartInfo = rustfs_filemeta::ObjectPartInfo;
 pub(crate) type ObjectLockBlockReason = ecstore_bucket::object_lock::objectlock_sys::ObjectLockBlockReason;

rustfs/src/storage_api.rs

@@ -147,8 +147,8 @@ pub(crate) mod server {
 
         #[cfg(test)]
         pub(crate) use crate::storage::storage_api::{
-            Endpoint, EndpointServerPools, Endpoints, PeerRestClient, PoolEndpoints, gen_signature_headers,
-            gen_tonic_signature_headers,
+            Endpoint, EndpointServerPools, Endpoints, PeerRestClient, PoolEndpoints, ScannerScopedDirtyUsageAckEntry,
+            gen_signature_headers, gen_tonic_signature_headers,
         };
 
         pub(crate) mod ecfs {

scripts/error-other-format-baseline.txt

@@ -45,7 +45,7 @@
 1|crates/ecstore/src/object_api/types.rs
 3|crates/ecstore/src/runtime/sources.rs
 4|crates/ecstore/src/services/batch_processor.rs
-14|crates/ecstore/src/services/notification_sys.rs
+13|crates/ecstore/src/services/notification_sys.rs
 16|crates/ecstore/src/services/rebalance/control.rs
 1|crates/ecstore/src/services/rebalance/entry.rs
 8|crates/ecstore/src/services/rebalance/meta.rs