if responses == nil {
		return nil, errors.New("RequestStream: responses channel is nil")
	}
	m.init = true
	m.respMu.Lock()
	if m.closed {
		m.respMu.Unlock()
		return nil, ErrDisconnected
	}
	m.respWait = responses // Route directly to output.
	m.respMu.Unlock()

	// Try to grab an initial block.
	m.singleResp = false
	m.RecvSeq = m.SendSeq // Sync
	if cap(requests) > 0 {

			ok = true
		}
	}
	if ok {
		lock := z.serverPools[0].NewNSLock(minioMetaBucket, rebalMetaName)
		lkCtx, err := lock.GetLock(ctx, globalOperationTimeout)
		if err != nil {
			rebalanceLogIf(ctx, fmt.Errorf("failed to acquire write lock on %s/%s: %w", minioMetaBucket, rebalMetaName, err))
			return err
		}
		defer lock.Unlock(lkCtx)

		ctx = lkCtx.Context()

	h.mu.RLock()
	defer h.mu.RUnlock()

	return h.Object
}

func (h *healingTracker) setObject(object string) {
	h.mu.Lock()
	defer h.mu.Unlock()

	h.Object = object
}

func (h *healingTracker) updateProgress(success, skipped bool, bytes uint64) {
	h.mu.Lock()
	defer h.mu.Unlock()

	switch {
	case success:
		h.ItemsHealed++
		h.BytesDone += bytes
	case skipped:
		h.ItemsSkipped++

}

func (t *tierMetrics) logSuccess(tier string) {
	t.Lock()
	defer t.Unlock()

	stat := t.requestsCount[tier]
	stat.success++
	t.requestsCount[tier] = stat
}

func (t *tierMetrics) logFailure(tier string) {
	t.Lock()
	defer t.Unlock()

	stat := t.requestsCount[tier]
	stat.failure++
	t.requestsCount[tier] = stat
}

var (

	}

	// if no update is needed return right away.
	if !update {
		z.poolMetaMutex.Lock()
		z.poolMeta = meta
		z.poolMetaMutex.Unlock()
	} else {
		newMeta := newPoolMeta(z, meta)
		if err = newMeta.save(ctx, z.serverPools); err != nil {
			return err
		}
		z.poolMetaMutex.Lock()
		z.poolMeta = newMeta
		z.poolMetaMutex.Unlock()
	}

	pools := meta.returnResumablePools()

 *
 * <ul>
 *   <li>for an unnested {@code lock()} and {@code unlock()}, a cycle detecting lock takes 38ns as
 *       opposed to the 24ns taken by a plain lock.
 *   <li>for nested locking, the cost increases with the depth of the nesting:
 *       <ul>
 *         <li>2 levels: average of 64ns per lock()/unlock()
 *         <li>3 levels: average of 77ns per lock()/unlock()
 *         <li>4 levels: average of 99ns per lock()/unlock()

	if r == nil {
		return
	}

	r.Lock()
	defer r.Unlock()
	delete(r.Cache, bucket)
}

// UpdateReplicaStat updates in-memory replica statistics with new values.
func (r *ReplicationStats) UpdateReplicaStat(bucket string, n int64) {
	if r == nil {
		return
	}

	r.Lock()
	defer r.Unlock()
	bs, ok := r.Cache[bucket]
	if !ok {
		bs = newBucketReplicationStats()

		}
		cancel(ErrDisconnected)
		c.connChange.L.Lock()
		if atomic.CompareAndSwapUint32((*uint32)(&c.state), StateConnected, StateConnectionError) {
			c.connChange.Broadcast()
		}
		c.disconnected()
		c.connChange.L.Unlock()

		conn.Close()
		c.handleMsgWg.Done()
	}()

	c.connMu.Lock()
	connPingInterval := c.connPingInterval
	c.connMu.Unlock()
	ping := time.NewTicker(connPingInterval)

			return ctx.Err()
		}
		if opts.Limit > 0 && objsReturned >= opts.Limit {
			return nil
		}

		if s.walkMu != nil {
			s.walkMu.Lock()
		}
		entries, err := s.ListDir(ctx, "", opts.Bucket, current, -1)
		if s.walkMu != nil {
			s.walkMu.Unlock()
		}
		if err != nil {
			// Folder could have gone away in-between
			if err != errVolumeNotFound && err != errFileNotFound {

					cancel()
					exit = true
				}
			}
			metaMu.Unlock()
		}
	}()

	const retryDelay = 200 * time.Millisecond
	const maxTries = 5

	// Keep destination...
	// Write results to disk.
	bw := newMetacacheBlockWriter(entries, func(b *metacacheBlock) error {
		// if the block is 0 bytes and its a first block skip it.
		// skip only this for Transient caches.