"Total capacity replicated to this instance",
				[]string{"bucket"}, nil),
			prometheus.GaugeValue,
			float64(stat.ReplicationStats.ReplicaSize),
			bucket,
		)

		for k, v := range usageInfo.ObjectSizesHistogram {
			ch <- prometheus.MustNewConstMetric(
				prometheus.NewDesc(
					prometheus.BuildFQName(bucketNamespace, "objects", "histogram"),
					"Total number of objects of different sizes in a bucket",

		bui := BucketUsageInfo{
			Size:                    uint64(flat.Size),
			VersionsCount:           flat.Versions,
			ObjectsCount:            flat.Objects,
			DeleteMarkersCount:      flat.DeleteMarkers,
			ObjectSizesHistogram:    flat.ObjSizes.toMap(),
			ObjectVersionsHistogram: flat.ObjVersions.toMap(),
		}
		dst[bucket.Name] = bui
	}
	return dst
}

// sizeRecursive returns the path as a flattened entry.