// NewNSLock - returns a lock instance for a given volume and
// path. The returned lockInstance object encapsulates the nsLockMap,
// volume, path and operation ID.
func (n *nsLockMap) NewNSLock(lockers func() ([]dsync.NetLocker, string), volume string, paths ...string) RWLocker {
	sort.Strings(paths)
	opsID := mustGetUUID()
	if n.isDistErasure {
		drwmutex := dsync.NewDRWMutex(&dsync.Dsync{
			GetLockers: lockers,

	// Start saver when object layer is ready.
	go func() {
		objAPI := newObjectLayerFn()
		for objAPI == nil {
			time.Sleep(time.Second)
			objAPI = newObjectLayerFn()
		}

		t := time.NewTicker(time.Minute)
		defer t.Stop()

		var exit bool
		for !exit {
			select {
			case <-t.C:
			case <-GlobalContext.Done():
				exit = true
			}
			m.mu.RLock()
			for _, v := range m.buckets {

func (m metacache) keepAlive(ctx context.Context, rpc *peerRESTClient) {
	// we intentionally operate on a copy of m, so we can update without locks.
	t := time.NewTicker(metacacheMaxClientWait / 10)
	defer t.Stop()
	for {
		select {
		case <-ctx.Done():
			// Request is done, stop updating.
			return
		case <-t.C:
			m.lastHandout = time.Now()

	if err == nil {
		return storageDisks, format, nil
	}

	tries++ // tried already once

	// Wait on each try for an update.
	ticker := time.NewTicker(1 * time.Second)
	defer ticker.Stop()

	for {
		// Only log once every 10 iterations, then reset the tries count.
		verbose = tries >= 10
		if verbose {
			tries = 1
		}

	} else {
		srs.XferRateSml.addSize(sz, duration)
	}
}

func newSRStats() *SRStats {
	s := SRStats{
		M:               make(map[string]*SRStatus),
		movingAvgTicker: time.NewTicker(time.Second * 2),
	}
	go s.trackEWMA()
	return &s
}

func (sr *SRStats) trackEWMA() {
	for {
		select {
		case <-sr.movingAvgTicker.C:
			sr.updateMovingAvg()
		case <-GlobalContext.Done():

			} else {
				write([]byte{0})
			}
			xioutil.SafeClose(doneCh)
			return
		}
		defer xioutil.SafeClose(doneCh)
		// Initiate ticker after body has been read.
		ticker := time.NewTicker(time.Second * 10)
		defer ticker.Stop()

		for {
			select {
			case <-ticker.C:
				// The done() might have been called
				// concurrently, check for it before we
				// write the filler byte.

		if tgt.Empty() {
			writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErrWithErr(ErrInvalidRequest, fmt.Errorf("invalid arn : '%s'", opts.ARN)), r.URL)
			return
		}
	}

	keepAliveTicker := time.NewTicker(500 * time.Millisecond)
	defer keepAliveTicker.Stop()

	diffCh, err := getReplicationDiff(ctx, objectAPI, bucket, opts)
	if err != nil {
		writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
		return

// Once the disk has been deemed ok, it will return to online status.
func (p *xlStorageDiskIDCheck) monitorDiskStatus(spent time.Duration, fn string) {
	t := time.NewTicker(5 * time.Second)
	defer t.Stop()

	for range t.C {
		if contextCanceled(p.diskCtx) {
			return
		}

		err := p.storage.WriteAll(context.Background(), minioMetaTmpBucket, fn, toWrite)

func (endpoints Endpoints) UpdateIsLocal() error {
	var epsResolved int
	var foundLocal bool
	resolvedList := make([]bool, len(endpoints))
	// Mark the starting time
	startTime := time.Now()
	keepAliveTicker := time.NewTicker(500 * time.Millisecond)
	defer keepAliveTicker.Stop()
	for !foundLocal && (epsResolved != len(endpoints)) {
		// Break if the local endpoint is found already Or all the endpoints are resolved.

	// it's decided to add functionality to close it in the version later than v2.
	if res.ttl != noEvictionTTL {
		go func(done <-chan struct{}) {
			ticker := time.NewTicker(res.ttl / numBuckets)
			defer ticker.Stop()
			for {
				select {
				case <-done:
					return
				case <-ticker.C:
					res.deleteExpired()
				}
			}
		}(res.done)
	}
	return &res
}