feat(ecstore): observe put commit lock wait (#6310)

crates/ecstore/Cargo.toml

@@ -267,6 +267,7 @@ tracing-subscriber = { workspace = true, features = ["json", "env-filter", "time
 # dispatcher to keep tracing's process-global callsite-interest cache honest.
 tracing-core = { workspace = true }
 serial_test = { workspace = true }
+metrics-util = { workspace = true, features = ["debugging"] }
 opentelemetry_sdk = { workspace = true, features = ["rt-tokio"] }
 proptest = "1"
 rcgen.workspace = true

crates/ecstore/src/set_disk/mod.rs

@@ -3264,6 +3264,17 @@ impl SetDisks {
         self.get_object_metadata_cache.invalidate_all();
     }
 
+    #[inline(always)]
+    fn record_put_object_commit_namespace_lock_wait(op: &'static str, acquire_start: Instant) {
+        if op != "put_object_commit" || !rustfs_io_metrics::put_stage_metrics_enabled() {
+            return;
+        }
+        rustfs_io_metrics::record_put_object_stage_duration_from(
+            rustfs_io_metrics::PUT_STAGE_PUT_OBJECT_COMMIT_NAMESPACE_LOCK_WAIT,
+            Some(acquire_start),
+        );
+    }
+
     async fn acquire_read_lock_diag(&self, op: &'static str, bucket: &str, object: &str) -> Result<ObjectLockDiagGuard> {
         crate::hp_guard!("SetDisks::acquire_read_lock");
         let diag_enabled = is_object_lock_diag_enabled();
@@ -3295,6 +3306,7 @@ impl SetDisks {
             .get_write_lock(get_lock_acquire_timeout())
             .await
             .map_err(|e| self.map_namespace_lock_error(bucket, object, "write", e))?;
+        Self::record_put_object_commit_namespace_lock_wait(op, acquire_start);
         let owner = diag_enabled.then(|| ns_lock.owner().to_string());
         self.log_object_lock_acquire_if_slow(
             op,
@@ -3342,6 +3354,7 @@ impl SetDisks {
         })
         .await
         .map_err(|e| self.map_namespace_lock_error(bucket, object, "write", e))?;
+        Self::record_put_object_commit_namespace_lock_wait(op, acquire_start);
         let owner = diag_enabled.then(|| ns_lock.owner().to_string());
         self.log_object_lock_acquire_if_slow(
             op,
@@ -5460,6 +5473,7 @@ mod tests {
     };
     use crate::store::init_format::save_format_file;
     use crate::store::list_objects::ListPathOptions;
+    use metrics_util::debugging::{DebugValue, DebuggingRecorder};
     use rustfs_filemeta::ErasureInfo;
     use rustfs_filemeta::FileMeta;
     use rustfs_filemeta::MetaCacheEntry;
@@ -5695,6 +5709,90 @@ mod tests {
         assert_eq!(Arc::strong_count(&set.set_lock_namespace), before);
     }
 
+    fn put_object_commit_namespace_lock_wait_sample_count(snapshotter: &metrics_util::debugging::Snapshotter) -> usize {
+        snapshotter
+            .snapshot()
+            .into_vec()
+            .into_iter()
+            .filter(|(composite, _, _, _)| {
+                composite.key().name() == "rustfs_s3_put_object_stage_duration_ms"
+                    && composite.key().labels().any(|label| {
+                        label.key().to_string() == "stage"
+                            && label.value().to_string() == rustfs_io_metrics::PUT_STAGE_PUT_OBJECT_COMMIT_NAMESPACE_LOCK_WAIT
+                    })
+            })
+            .map(|(_, _, _, value)| match value {
+                DebugValue::Histogram(samples) => samples.len(),
+                _ => 0,
+            })
+            .sum()
+    }
+
+    #[test]
+    #[serial]
+    fn put_object_commit_namespace_lock_wait_metric_is_wired_to_both_write_lock_paths() {
+        let recorder = DebuggingRecorder::new();
+        let snapshotter = recorder.snapshotter();
+        let runtime = tokio::runtime::Builder::new_current_thread()
+            .enable_all()
+            .build()
+            .expect("test runtime should start");
+
+        metrics::with_local_recorder(&recorder, || {
+            runtime.block_on(async {
+                let ctx = Arc::new(InstanceContext::new());
+                ctx.update_erasure_type(SetupType::Erasure).await;
+                let set = make_test_set_disks_with_ctx(Vec::new(), ctx).await;
+                let bucket = "bucket";
+                let object = "object";
+
+                rustfs_io_metrics::set_put_stage_metrics_enabled(false);
+                let guard = set
+                    .acquire_write_lock_diag("put_object_commit", bucket, object)
+                    .await
+                    .expect("disabled metrics acquire should succeed");
+                drop(guard);
+                assert_eq!(put_object_commit_namespace_lock_wait_sample_count(&snapshotter), 0);
+
+                rustfs_io_metrics::set_put_stage_metrics_enabled(true);
+                let guard = set
+                    .acquire_write_lock_diag("put_object_commit", bucket, object)
+                    .await
+                    .expect("normal PUT commit acquire should succeed");
+                drop(guard);
+                assert_eq!(put_object_commit_namespace_lock_wait_sample_count(&snapshotter), 1);
+
+                let guard = set
+                    .acquire_write_lock_diag("complete_multipart_upload_commit", bucket, object)
+                    .await
+                    .expect("non-PUT commit acquire should succeed");
+                drop(guard);
+                assert_eq!(put_object_commit_namespace_lock_wait_sample_count(&snapshotter), 0);
+
+                let held_guard = set
+                    .acquire_write_lock_diag("put_object_commit", bucket, object)
+                    .await
+                    .expect("holder acquire should succeed");
+                assert_eq!(put_object_commit_namespace_lock_wait_sample_count(&snapshotter), 1);
+
+                let (pending_tx, pending_rx) = tokio::sync::oneshot::channel();
+                let pending_acquire =
+                    set.acquire_write_lock_diag_with_pending_hook("put_object_commit", bucket, object, move || {
+                        let _ = pending_tx.send(());
+                    });
+                let release_holder = async {
+                    pending_rx.await.expect("pending hook should fire");
+                    drop(held_guard);
+                };
+                let (pending_guard, ()) = tokio::join!(pending_acquire, release_holder);
+                drop(pending_guard.expect("pending-hook PUT commit acquire should succeed"));
+                assert_eq!(put_object_commit_namespace_lock_wait_sample_count(&snapshotter), 1);
+
+                rustfs_io_metrics::set_put_stage_metrics_enabled(false);
+            });
+        });
+    }
+
     #[tokio::test]
     async fn new_ns_lock_shares_clients_without_changing_quorum() {
         let healthy: Arc<dyn LockClient> = Arc::new(LocalClient::with_manager(Arc::new(rustfs_lock::GlobalLockManager::new())));