)

var erasureHealTests = []struct {
	dataBlocks, disks int

	// number of offline disks is also number of staleDisks for
	// erasure reconstruction in this test
	offDisks int

	// bad disks are online disks which return errors
	badDisks, badStaleDisks int

	blocksize, size int64
	algorithm       BitrotAlgorithm
	shouldFail      bool
}{

	// However many we ask, versions must exist on ~50%
	listingQuorum := (askDisks + 1) / 2

	if askDisks > 0 && len(disks) > askDisks {
		rand.Shuffle(len(disks), func(i, j int) {
			disks[i], disks[j] = disks[j], disks[i]
		})
		fallbackDisks = disks[askDisks:]
		disks = disks[:askDisks]
	}

	// How to resolve results.
	resolver := metadataResolutionParams{
		dirQuorum: listingQuorum,
		objQuorum: listingQuorum,

if (disks not recognized) // Always error.

// Specific checks.
if (all disks online)
  if (all disks return format.json)
     if (jbod consistent)
        if (all disks recognized)
          return
  else
     if (all disks return format.json not found)
        return error
     else (some disks return format.json not found)
        (heal format)
        return
     fi
   fi
else

		err := fmt.Errorf("unexpected file distribution (%v) from online disks (%v), looks like backend disks have been manually modified refusing to heal %s/%s(%s)",
			latestMeta.Erasure.Distribution, onlineDisks, bucket, object, versionID)
		healingLogOnceIf(ctx, err, "heal-object-online-disks")
		return er.defaultHealResult(latestMeta, storageDisks, storageEndpoints, errs,
			bucket, object, versionID), err

		}

		// Step 3: Upload the object with some disks offline
		sets.erasureDisksMu.Lock()
		xl.getDisks = func() []StorageAPI {
			disks := make([]StorageAPI, len(origErasureDisks))
			copy(disks, origErasureDisks)
			disks[0] = nil
			disks[1] = nil
			return disks
		}
		sets.erasureDisksMu.Unlock()

}

func writeAllMetadataWithRevert(ctx context.Context, disks []StorageAPI, origbucket, bucket, prefix string, files []FileInfo, quorum int, revert bool) ([]StorageAPI, error) {
	g := errgroup.WithNErrs(len(disks))

	// Start writing `xl.meta` to all disks in parallel.
	for index := range disks {
		g.Go(func() error {
			if disks[index] == nil {
				return errDiskNotFound
			}

	result.Delimiter = delimiter

	var uploadIDs []string
	var disk StorageAPI
	disks := er.getOnlineLocalDisks()
	if len(disks) == 0 {
		// If no local, get non-healing disks.
		var ok bool
		if disks, ok = er.getOnlineDisksWithHealing(false); !ok {
			disks = er.getOnlineDisks()
		}
	}

	for _, disk = range disks {
		if disk == nil {
			continue
		}
		if !disk.IsOnline() {
			continue
		}

    int nThreads = 20;
    int tasksPerThread = 10;
    int nTasks = nThreads * tasksPerThread;
    ExecutorService pool = newFixedThreadPool(nThreads);
    ImmutableList<String> keys = ImmutableList.of("a", "b", "c");
    try {
      List<Future<int[]>> futures = newArrayListWithExpectedSize(nTasks);
      for (int i = 0; i < nTasks; i++) {
        futures.add(pool.submit(new MutateTask(multiset, keys)));
      }

	})
}

func readAllRawFileInfo(ctx context.Context, disks []StorageAPI, bucket, object string, readData bool) ([]RawFileInfo, []error) {
	rawFileInfos := make([]RawFileInfo, len(disks))
	g := errgroup.WithNErrs(len(disks))
	for index := range disks {
		g.Go(func() (err error) {
			if disks[index] == nil {
				return errDiskNotFound
			}
			rf, err := disks[index].ReadXL(ctx, bucket, object, readData)
			if err != nil {

	diskPaths    []string
	disks        []StorageAPI
}

// Returns an initialized setup for erasure tests.
func newErasureTestSetup(tb testing.TB, dataBlocks int, parityBlocks int, blockSize int64) (*erasureTestSetup, error) {
	diskPaths := make([]string, dataBlocks+parityBlocks)
	disks := make([]StorageAPI, len(diskPaths))
	var err error
	for i := range diskPaths {
		disks[i], diskPaths[i], err = newXLStorageTestSetup(tb)