diff --git a/xl-erasure-v1.go b/xl-erasure-v1.go index 3e1f39dba..334d3df8f 100644 --- a/xl-erasure-v1.go +++ b/xl-erasure-v1.go @@ -262,48 +262,58 @@ func (xl XL) DeleteVol(volume string) error { // ListVols - list volumes. func (xl XL) ListVols() (volsInfo []VolInfo, err error) { emptyCount := 0 - // Success vols map carries successful results of ListVols from - // each disks. - var successVolsMap = make(map[int][]VolInfo) + + // Initialize sync waitgroup. + var wg = &sync.WaitGroup{} + + // Success vols map carries successful results of ListVols from each disks. + var successVols = make([][]VolInfo, len(xl.storageDisks)) for index, disk := range xl.storageDisks { - var vlsInfo []VolInfo - vlsInfo, err = disk.ListVols() - if err == nil { - if len(vlsInfo) == 0 { - emptyCount++ - } else { - successVolsMap[index] = vlsInfo + wg.Add(1) // Add each go-routine to wait for. + go func(index int, disk StorageAPI) { + // Indicate wait group as finished. + defer wg.Done() + + // Initiate listing. + vlsInfo, lErr := disk.ListVols() + if lErr == nil { + if len(vlsInfo) == 0 { + emptyCount++ // Calculate empty count specially. + } else { + successVols[index] = vlsInfo + } } - } + }(index, disk) } + // For all the list volumes running in parallel to finish. + wg.Wait() // If all list operations resulted in an empty count which is same // as your total storage disks, then it is a valid case return // success with empty vols. if emptyCount == len(xl.storageDisks) { return []VolInfo{}, nil - } else if len(successVolsMap) < xl.readQuorum { + } else if len(successVols) < xl.readQuorum { // If there is data and not empty, then we attempt quorum verification. // Verify if we have enough quorum to list vols. return nil, errReadQuorum } var total, free int64 - // Loop through success vols map and get aggregated usage values. - for index := range xl.storageDisks { - if _, ok := successVolsMap[index]; ok { - volsInfo = successVolsMap[index] - free += volsInfo[0].Free - total += volsInfo[0].Total - } - } - // Save the updated usage values back into the vols. - for index := range volsInfo { - volsInfo[index].Free = free - volsInfo[index].Total = total + // Loop through success vols and get aggregated usage values. + for _, vlsInfo := range successVols { + free += vlsInfo[0].Free + total += vlsInfo[0].Total } - // TODO: the assumption here is that volumes across all disks in + // Save the updated usage values back into the vols. + for _, volInfo := range successVols[0] { + volInfo.Free = free + volInfo.Total = total + volsInfo = append(volsInfo, volInfo) + } + + // NOTE: The assumption here is that volumes across all disks in // readQuorum have consistent view i.e they all have same number // of buckets. This is essentially not verified since healing // should take care of this.