dm.Unlock(context.Background())
}

func TestSimpleLockUnlockMultipleTimes(t *testing.T) {
	dm := NewDRWMutex(ds, "test")

	dm.Lock(id, source)
	time.Sleep(time.Duration(10+(rand.Float32()*50)) * time.Millisecond)
	dm.Unlock(context.Background())

	dm.Lock(id, source)
	time.Sleep(time.Duration(10+(rand.Float32()*50)) * time.Millisecond)
	dm.Unlock(context.Background())

	dm.Lock(id, source)

	return concat(s, strconv.Itoa(idx))
}

func (l *localLocker) Unlock(_ context.Context, args dsync.LockArgs) (reply bool, err error) {
	if len(args.Resources) > maxDeleteList {
		return false, fmt.Errorf("internal error: localLocker.Unlock called with more than %d resources", maxDeleteList)
	}

	l.mutex.Lock()
	defer l.mutex.Unlock()
	err = nil

	for _, resource := range args.Resources {

		if err = NetnsSet(fdable); err != nil {
			return err
		}
		defer func() {
			err := threadNS.Set() // switch back
			if err == nil {
				// Unlock the current thread only when we successfully switched back
				// to the original namespace; otherwise leave the thread locked which
				// will force the runtime to scrap the current thread, that is maybe
				// not as optimal but at least always safe to do.
				runtime.UnlockOSThread()

// from a placeholder node "arg_tensor_enqueue_<tensor_id>".
//
// `tensor` is still owned by the caller. This call will be blocked if the queue
// has reached its capacity, and will be unblocked when the queued tensors again
// drop below the capacity due to dequeuing.
//
// Tensors are dequeued via the corresponding TF dequeue op.
// TODO(hongm): Add support for `timeout_ms`.

		sys.group.Forget(bucket)
		delete(sys.metadataMap, bucket)
		globalBucketMonitor.DeleteBucket(bucket)
	}
	sys.Unlock()
}

// RemoveStaleBuckets removes all stale buckets in memory that are not on disk.
func (sys *BucketMetadataSys) RemoveStaleBuckets(diskBuckets set.StringSet) {
	sys.Lock()
	defer sys.Unlock()

	for bucket := range sys.metadataMap {
		if diskBuckets.Contains(bucket) {
			continue

			}
			if state == StateShutdown || state == StateConnectionError {
				c.connChange.L.Unlock()
				return
			}
			c.connChange.Wait()
			select {
			case <-ctx.Done():
				c.connChange.L.Unlock()
				return
			default:
			}
		}
		c.connChange.L.Unlock()
		if len(queue) == 0 {
			// Send single message without merging.

		globalHTTPStats.incS3RequestsIncoming()

		if r.Header.Get(globalObjectPerfUserMetadata) == "" {
			if val := globalServiceFreeze.Load(); val != nil {
				if unlock, ok := val.(chan struct{}); ok && unlock != nil {
					// Wait until unfrozen.
					select {
					case <-unlock:
					case <-r.Context().Done():
						// if client canceled we don't need to wait here forever.
						return
					}
				}
			}
		}

	readers := make([]*metacacheReader, len(disks))
	defer func() {
		for _, r := range readers {
			r.Close()
		}
	}()
	for i := range disks {
		r, w := io.Pipe()
		// Make sure we close the pipe so blocked writes doesn't stay around.
		defer r.CloseWithError(context.Canceled)

		readers[i] = newMetacacheReader(r)
		d := disks[i]

		// Send request to each disk.
		go func() {
			var werr error

					}
				} else {
					onlineServers++
				}
				mu.Unlock()
			}(clnt)
		}
		wg.Wait()

		select {
		case <-ctx.Done():
			return ctx.Err()
		default:
			// Sleep and stagger to avoid blocked CPU and thundering
			// herd upon start up sequence.
			time.Sleep(25*time.Millisecond + time.Duration(rand.Int63n(int64(100*time.Millisecond))))

	}
	// A UID is added for every resource.
	// We removed Add Rlocked entries
	if len(l.lockUID) != len(wResources)*m {
		t.Fatalf("lockUID len, got %d, want %d + %d", len(l.lockUID), 0, len(wResources)*m)
	}

	// Remove write locked
	for i, names := range wResources {
		arg := dsync.LockArgs{
			UID:       wUIDs[i],
			Resources: names[:],