cachevalue.Opts{ReturnLastGood: true, NoWait: true},
		func() (DataUsageInfo, error) {
			ctx, done := context.WithTimeout(context.Background(), 2*time.Second)
			defer done()

			return loadDataUsageFromBackend(ctx, objAPI)
		},
	)
}

// GetBucketUsageInfo return bucket usage info for a given bucket
func (sys *BucketQuotaSys) GetBucketUsageInfo(bucket string) (BucketUsageInfo, error) {

							m[prefix] += uint64(usageInfo.Size)
						}
					}
				}
			}
			return m, nil
		},
	)

	return prefixUsageCache.Get()
}

func loadDataUsageFromBackend(ctx context.Context, objAPI ObjectLayer) (DataUsageInfo, error) {
	buf, err := readConfig(ctx, objAPI, dataUsageObjNamePath)
	if err != nil {
		buf, err = readConfig(ctx, objAPI, dataUsageObjNamePath+".bkp")

	loadDataUsage := func() (u DataUsageInfo, err error) {
		objLayer := newObjectLayerFn()
		if objLayer == nil {
			return
		}

		// Collect cluster level object metrics.
		u, err = loadDataUsageFromBackend(GlobalContext, objLayer)
		return
	}
	return cachevalue.NewFromFunc(1*time.Minute,
		cachevalue.Opts{ReturnLastGood: true},
		loadDataUsage)
}

	ctx := r.Context()

	objAPI, _ := validateAdminReq(ctx, w, r, policy.ListTierAction)
	if objAPI == nil {
		return
	}

	dui, err := loadDataUsageFromBackend(ctx, objAPI)
	if err != nil {
		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, err), r.URL)
		return
	}

	tierStats := dui.tierStats()
	dailyStats := globalNotificationSys.GetLastDayTierStats(ctx)

func bucketUsageMetricsPrometheus(ch chan<- prometheus.Metric) {
	objLayer := newObjectLayerFn()
	// Service not initialized yet
	if objLayer == nil {
		return
	}

	dataUsageInfo, err := loadDataUsageFromBackend(GlobalContext, objLayer)
	if err != nil {
		return
	}
	// data usage has not captured any data yet.
	if dataUsageInfo.LastUpdate.IsZero() {
		return
	}

	ctx := r.Context()

	objectAPI, _ := validateAdminReq(ctx, w, r, policy.DataUsageInfoAdminAction)
	if objectAPI == nil {
		return
	}

	dataUsageInfo, err := loadDataUsageFromBackend(ctx, objectAPI)
	if err != nil {
		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, err), r.URL)
		return
	}

	dataUsageInfoJSON, err := json.Marshal(dataUsageInfo)
	if err != nil {

		objLayer := newObjectLayerFn()
		if objLayer == nil {
			return
		}

		metrics = make([]MetricV2, 0, 50)
		dataUsageInfo, err := loadDataUsageFromBackend(ctx, objLayer)
		if err != nil {
			metricsLogIf(ctx, err)
			return
		}

		// data usage has not captured any data yet.
		if dataUsageInfo.LastUpdate.IsZero() {
			return
		}

		cachevalue.Opts{ReturnLastGood: true, NoWait: true},
		func() (DataUsageInfo, error) {
			ctx, done := context.WithTimeout(context.Background(), 2*time.Second)
			defer done()

			return loadDataUsageFromBackend(ctx, objectAPI)
		},
	)

	dataUsageInfo, _ := bucketStorageCache.Get()

	// If etcd, dns federation configured list buckets from etcd.
	var err error
	var buckets []BucketInfo