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 {

}

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()

	sys.aMutex.Lock()
	defer sys.aMutex.Unlock()
	if v, ok := sys.arnErrsMap[arn]; !ok {
		sys.arnErrsMap[arn] = arnErrs{
			updateInProgress: true,
			count:            v.count + 1,
			bucket:           bucket,
		}
	}
}

func (sys *BucketTargetSys) markRefreshDone(bucket, arn string) {
	sys.aMutex.Lock()
	defer sys.aMutex.Unlock()
	if v, ok := sys.arnErrsMap[arn]; ok {

			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()

	var funcReturnedMu sync.Mutex
	defer func() {
		funcReturnedMu.Lock()
		funcReturned = true
		funcReturnedMu.Unlock()
	}()
	// Write listing to results and saver.
	go func() {
		var returned bool
		for entry := range inCh {
			if !returned {
				funcReturnedMu.Lock()
				returned = funcReturned
				funcReturnedMu.Unlock()
				outCh <- entry
				if returned {
					xioutil.SafeClose(outCh)

}

// Unlock unlocks the write lock.
//
// It is a run-time error if dm is not locked on entry to Unlock.
func (dm *DRWMutex) Unlock(ctx context.Context) {
	dm.m.Lock()
	dm.cancelRefresh()
	dm.m.Unlock()

	restClnts, owner := dm.clnt.GetLockers()
	// create temp array on stack
	locks := make([]string, len(restClnts))

	{
		dm.m.Lock()
		defer dm.m.Unlock()

	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)
	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)

func (sys *BucketMetadataSys) Count() int {
	sys.RLock()
	defer sys.RUnlock()

	return len(sys.metadataMap)
}

// Remove bucket metadata from memory.
func (sys *BucketMetadataSys) Remove(buckets ...string) {
	sys.Lock()
	for _, bucket := range buckets {
		delete(sys.metadataMap, bucket)
		globalBucketMonitor.DeleteBucket(bucket)
	}
	sys.Unlock()
}

		t.Fatal(err)
	}

	erasureDisks := xl.getDisks()
	z.serverPools[0].erasureDisksMu.Lock()
	xl.getDisks = func() []StorageAPI {
		for i := range erasureDisks[:6] {
			erasureDisks[i] = newNaughtyDisk(erasureDisks[i], nil, errFaultyDisk)
		}
		return erasureDisks
	}

	z.serverPools[0].erasureDisksMu.Unlock()
	_, err = obj.DeleteObject(ctx, bucket, object, ObjectOptions{})