// Updates are sent on a regular basis and the caller *must* consume them.
func (er erasureObjects) nsScanner(ctx context.Context, buckets []BucketInfo, wantCycle uint32, updates chan<- dataUsageCache, healScanMode madmin.HealScanMode) error {
	if len(buckets) == 0 {
		return nil
	}

	// Collect disks we can use.
	disks, healing := er.getOnlineDisksWithHealing(false)
	if len(disks) == 0 {

	defer n.Unlock()
	n.RX = 0
	n.RXSample = 0
	n.lastToConnect = time.Time{}
	n.firstToDisconnect = time.Time{}
}

// Reader to read random data.
type netperfReader struct {
	n   uint64
	eof chan struct{}
	buf []byte
}

func (m *netperfReader) Read(b []byte) (int, error) {
	select {
	case <-m.eof:
		return 0, io.EOF
	default:
	}
	n := copy(b, m.buf)
	atomic.AddUint64(&m.n, uint64(n))

	desc *prometheus.Desc
}

// Describe sends the super-set of all possible descriptors of metrics
func (c *minioCollector) Describe(ch chan<- *prometheus.Desc) {
	ch <- c.desc
}

// Collect is called by the Prometheus registry when collecting metrics.
func (c *minioCollector) Collect(ch chan<- prometheus.Metric) {
	// Expose MinIO's version information
	minioVersionInfo.WithLabelValues(Version, CommitID).Set(1.0)

	es := &expiryState{
		ctx:    ctx,
		objAPI: objAPI,
	}
	workers := make([]chan expiryOp, 0, n)
	es.workers.Store(&workers)
	es.ResizeWorkers(n)
	return es
}

func (es *expiryState) getWorkerCh(h uint64) chan<- expiryOp {
	w := es.workers.Load()
	if w == nil || len(*w) == 0 {
		return nil
	}
	workers := *w

	if !s.checkID(params.DiskID) {
		return grid.NewRemoteErr(errDiskNotFound)
	}
	if params.Cache == nil {
		return grid.NewRemoteErrString("NSScannerHandler: provided cache is nil")
	}

	// Collect updates, stream them before the full cache is sent.
	updates := make(chan dataUsageEntry, 1)
	var wg sync.WaitGroup
	wg.Add(1)

// Borrowed from mutex_test.go
func HammerMutex(m *DRWMutex, loops int, cdone chan bool) {
	for i := 0; i < loops; i++ {
		m.Lock(id, source)
		m.Unlock(context.Background())
	}
	cdone <- true
}

// Borrowed from mutex_test.go
func TestMutex(t *testing.T) {
	loops := 200
	if testing.Short() {
		loops = 5
	}
	c := make(chan bool)
	m := NewDRWMutex(ds, "test")
	for i := 0; i < 10; i++ {

	name := newTgt.Name()

	currentBuff, ok := logChBuffers[name]
	if !ok {
		logChBuffers[name] = make(chan interface{}, requiredCap)
		currentCap = requiredCap
	} else {
		currentCap = cap(currentBuff)
		requiredCap += len(currentBuff)
	}

	if requiredCap > currentCap {
		logChBuffers[name] = make(chan interface{}, requiredCap)

		if len(currentBuff) > 0 {
		drain:
			for {
				select {

//           value: image/* # match objects with 'content-type', all values starting with 'image/'
//       size:
//         lessThan: "10MiB" # match objects with size less than this value (e.g. 10MiB)
//         greaterThan: 1MiB # match objects with size greater than this value (e.g. 1MiB)
//       purge:
//           # retainVersions: 0 # (default) delete all versions of the object. This option is the fastest.

}

type updateRequest struct {
	Update []byte
	Fd     *int

	Resp chan updateResponse
}

type ZtunnelConnection struct {
	u       *net.UnixConn
	Updates chan updateRequest
}

func newZtunnelConnection(u *net.UnixConn) *ZtunnelConnection {
	return &ZtunnelConnection{u: u, Updates: make(chan updateRequest, 100)}
}

func (z *ZtunnelConnection) Close() {
	z.u.Close()
}

		// Register a single handler which echos the payload.
		errFatal(remote.RegisterStreamingHandler(handlerTest, StreamHandler{
			// Send 10x response.
			Handle: func(ctx context.Context, payload []byte, _ <-chan []byte, out chan<- []byte) *RemoteErr {
				for i := 0; i < responses; i++ {
					toSend := GetByteBuffer()[:0]
					toSend = append(toSend, byte(i))
					toSend = append(toSend, payload...)
					select {