if root == nil {
							// We dont have usage information for this bucket in this
							// set, go to the next set
							continue
						}

						for id, usageInfo := range cache.flattenChildrens(*root) {
							prefix := decodeDirObject(strings.TrimPrefix(id, bucket+slashSeparator))
							// decodeDirObject to avoid any __XLDIR__ objects
							m[prefix] += uint64(usageInfo.Size)
						}
					}
				}