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))))
			retries++
			// after 20 retries start logging that servers are not reachable yet
			if retries >= 20 {

	r := rand.New(rand.NewSource(UTCNow().UnixNano()))

	buf := &bytes.Buffer{}

	// Verify erasure.Decode() for random offsets and lengths.
	for i := 0; i < iterations; i++ {
		offset := r.Int63n(length)
		readLen := r.Int63n(length - offset)

		expected := data[offset : offset+readLen]

		// Get the checksums of the current part.
		bitrotReaders := make([]io.ReaderAt, len(disks))
		for index, disk := range disks {

				p.health.waiting.Add(1)
				go p.monitorDiskStatus(spent, fn)
			}
		}

		// Offset checks a bit.
		time.Sleep(time.Duration(rng.Int63n(int64(1 * time.Second))))

		dctx, dcancel := context.WithCancel(ctx)
		started := time.Now()
		go func() {
			timeout := time.NewTimer(globalDriveConfig.GetMaxTimeout())
			select {
			case <-dctx.Done():

type lockedRandSource struct {
	lk  sync.Mutex
	src rand.Source
}

// Int63 returns a non-negative pseudo-random 63-bit integer as an int64.
func (r *lockedRandSource) Int63() (n int64) {
	r.lk.Lock()
	n = r.src.Int63()
	r.lk.Unlock()
	return
}

// Seed uses the provided seed value to initialize the generator to a
// deterministic state.

		c.connMu.Unlock()
		retry := func(err error) {
			if debugPrint {
				fmt.Printf("%v Connecting to %v: %v. Retrying.\n", c.Local, toDial, err)
			}
			sleep := defaultDialTimeout + time.Duration(rng.Int63n(int64(defaultDialTimeout)))
			next := dialStarted.Add(sleep / 2)
			sleep = time.Until(next).Round(time.Millisecond)
			if sleep < 0 {
				sleep = 0
			}
			gotState := c.State()

		cancel()
		if err == nil {
			break
		}
		if minio.ToErrorResponse(err).Code == "PreconditionFailed" {
			return err
		}
		attempts++
		time.Sleep(time.Duration(rand.Int63n(int64(time.Second))))
	}
	if err != nil {
		return err
	}

	defer func() {
		if err != nil {
			// block and abort remote upload upon failure.
			attempts := 1
			for attempts <= 3 {

	for index := range buckets {
		index := index
		g.Go(func() error {
			// 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))))

			_, _ = sys.objAPI.HealBucket(ctx, buckets[index].Name, madmin.HealOpts{Recreate: true})
			meta, err := loadBucketMetadata(ctx, sys.objAPI, buckets[index].Name)
			if err != nil {

var src = rand.NewSource(time.Now().UnixNano())

func randString(n int) string {
	b := make([]byte, n)
	// A src.Int63() generates 63 random bits, enough for letterIdxMax characters!
	for i, cache, remain := n-1, src.Int63(), letterIdxMax; i >= 0; {
		if remain == 0 {
			cache, remain = src.Int63(), letterIdxMax
		}
		if idx := int(cache & letterIdxMask); idx < len(letterBytes) {
			b[i] = letterBytes[idx]
			i--

	// 4 MB block.
	// Approx runtime ~30ms
	data := make([]byte, 4<<20)
	rng := rand.New(rand.NewSource(0))
	for i := range data {
		// Generate compressible stream...
		data[i] = byte(rng.Int63() & 3)
	}
	failOnErr := func(err error) {
		if err != nil {
			logger.Fatal(errSelfTestFailure, "compress: error on self-test: %v", err)
		}
	}
	const skip = 2<<20 + 511

		}
		retry, err = load(name+".bkp", 30*time.Second)
		if err == nil && !retry {
			// Only return when we have valid data from the backup
			break
		}
		retries++
		time.Sleep(time.Duration(rand.Int63n(int64(time.Second))))
	}

	if retries == 5 {
		scannerLogOnceIf(ctx, fmt.Errorf("maximum retry reached to load the data usage cache `%s`", name), "retry-loading-data-usage-cache")
	}

	return nil
}