wait()
					return nil
				})
			})
		}(disk)
	}
	wg.Wait()
}

// nsScanner will start scanning buckets and send updated totals as they are traversed.
// 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 {

type ObjectLayer interface {
	// Locking operations on object.
	NewNSLock(bucket string, objects ...string) RWLocker

	// Storage operations.
	Shutdown(context.Context) error
	NSScanner(ctx context.Context, updates chan<- DataUsageInfo, wantCycle uint32, scanMode madmin.HealScanMode) error
	BackendInfo() madmin.BackendInfo

func (client *storageRESTClient) Healing() *healingTracker {
	// This call is not implemented for remote client on purpose.
	// healing tracker is always for local disks.
	return nil
}

func (client *storageRESTClient) NSScanner(ctx context.Context, cache dataUsageCache, updates chan<- dataUsageEntry, scanMode madmin.HealScanMode, _ func() bool) (dataUsageCache, error) {
	defer xioutil.SafeClose(updates)

	return storageInfo
}

func (z *erasureServerPools) StorageInfo(ctx context.Context, metrics bool) StorageInfo {
	return globalNotificationSys.StorageInfo(ctx, z, metrics)
}

func (z *erasureServerPools) NSScanner(ctx context.Context, updates chan<- DataUsageInfo, wantCycle uint32, healScanMode madmin.HealScanMode) error {
	// Updates must be closed before we return.
	defer xioutil.SafeClose(updates)

			}

			// Wait before starting next cycle and wait on startup.
			results := make(chan DataUsageInfo, 1)
			go storeDataUsageInBackend(ctx, objAPI, results)
			err := objAPI.NSScanner(ctx, results, uint32(cycleInfo.current), scanMode)
			scannerLogIf(ctx, err)
			res := map[string]string{"cycle": strconv.FormatUint(cycleInfo.current, 10)}
			if err != nil {
				res["error"] = err.Error()
			}