fix(lock): fence write commit on lock loss (backlog#899 Phase 2)
Phase 0+1 (#4388) made object write locks refreshable and marks the guard
lost when the heartbeat can no longer refresh a quorum, but does not act on
it. Under a partition a long write's lock can expire on an unreachable node
and be reclaimed, letting a third party re-acquire it; the original writer
keeps going and both commit -- a double write.
Expose the loss signal through NamespaceLockGuard::is_lock_lost() and
ObjectLockDiagGuard::is_lock_lost(), and fence the commit in put_object and
complete_multipart_upload: immediately before rename_data (the atomic commit
point), abort with a retryable NamespaceLockQuorumUnavailable (503) if the
lock was lost. In multipart the check precedes cleanup_multipart_path so a
lost lock leaves the upload intact and retryable. A write that already
reached rename_data Ok is durable and never aborted.
The loss criterion is unchanged (reacts to Phase 1's signal). Heal and the
long-GET read side are deferred follow-ups.
fix(lock): renew distributed locks via heartbeat; wire server refresh (backlog#899)
A held distributed write lock had a fixed 30s TTL and was never renewed, so
any operation exceeding it got its per-node lease reclaimed and stolen by a
contender, causing split-brain writes. This implements Phase 0 + Phase 1 of the
#899 design (Phase 2 abort-on-loss is deferred and tracked in code comments).
Phase 0 (server refresh wiring, P0):
- node_service handle_refresh was a no-op stub that parsed args then always
returned success=true. Extract a testable `refresh_lock` free function that
actually delegates to the node's lock backend. Not-found maps to
success=false with no error_info, so RemoteClient::refresh keeps its
Ok(resp.success) semantics and yields a real not_found signal to the
coordinator heartbeat. Without this, client heartbeats were silently no-ops.
Phase 1 (client heartbeat + safe interval + observability):
- DistributedLockGuard spawns a heartbeat that refreshes every per-client lease
on a derived interval; interval is derived without Duration::clamp
(entries<=1 or interval>=ttl => no spawn), fixing the sub-second-ttl panic.
- Add LockLostSignal: declare the lock lost when not_found exceeds
entries.len() - refresh_quorum; RPC errors are not counted (absorbed by the
ttl > interval margin). Expose is_lock_lost()/lock_lost() for observers.
- disarm(), release(), and Drop now abort the heartbeat before releasing so no
refresh races the unlock (refresh only extends, never creates, a lease).
- Reclaim path stays behaviorally unchanged but now warns with owner/resource/
lease age and records a metric (#698 scavenger preserved).
- Add DEFAULT_LOCK_REFRESH_INTERVAL, LockRequest.refresh_interval (serde default
for RPC back-compat) + builder, and lock lifecycle metrics.
Open questions adopt the design's documented defaults (marked TODO in code):
refresh not-found -> Ok(false)/error_info=None; lost-quorum base entries.len();
DEFAULT_LOCK_REFRESH_INTERVAL=10s.
Tests: heartbeat keepalive/quorum-loss/jitter/boundary/disarm (lock crate),
server refresh delegation (rustfs), and end-to-end survives-past-ttl plus
crashed-owner-reclaim regressions (namespace).
* feat(ecstore): add object lock diagnostics
Add configurable namespace lock diagnostics for object operations so production contention can be traced by operation, owner, and key.
Wrap object read/write lock acquisition in diagnostic guards across get, head, put, delete, copy, and multipart flows, and log slow acquisition and long hold durations behind new RUSTFS_OBJECT_LOCK_DIAG_* settings.
Verification:
- make pre-commit
* feat(obs): expose object lock diagnostics metrics
Add Prometheus metrics and Grafana panels for object namespace lock diagnostics, covering slow acquire counts, slow hold counts, acquire duration, hold duration, and the diagnostics-enabled state.
Adopt PR review feedback by keeping diagnostic guards alive through the guarded operation so long-hold warnings and metrics are emitted, reusing shared env helpers, and reducing default-path overhead when diagnostics are disabled.
Verification:
- cargo check -p rustfs-ecstore -p rustfs-io-metrics
- cargo test -p rustfs-ecstore store::object -- --nocapture
- make pre-commit
* perf(obs): reduce object lock diag overhead
Avoid repeated environment parsing on hot object-lock paths by caching the diagnostics-enabled flag, and stop allocating label strings for object lock metrics by recording static labels directly.
Strengthen io-metrics tests by using a local recorder and asserting that the expected object lock diagnostic counters, gauges, and histograms are emitted.
Verification:
- cargo check -p rustfs-ecstore -p rustfs-io-metrics
- cargo test -p rustfs-io-metrics -- --nocapture
- make pre-commit
Zhengchao An