case size < fi.Erasure.BlockSize:
		// No need to allocate fully fi.Erasure.BlockSize buffer if the incoming data is smaller.
		buffer = make([]byte, size, 2*size+int64(fi.Erasure.ParityBlocks+fi.Erasure.DataBlocks-1))
	}

	if len(buffer) > int(fi.Erasure.BlockSize) {
		buffer = buffer[:fi.Erasure.BlockSize]
	}
	writers := make([]io.Writer, len(onlineDisks))
	for i, disk := range onlineDisks {
		if disk == nil {

	if totalLength == -1 {
		return -1
	}
	numShards := totalLength / e.BlockSize
	lastBlockSize := totalLength % e.BlockSize
	lastShardSize := ceilFrac(lastBlockSize, int64(e.DataBlocks))
	return numShards*e.ShardSize() + lastShardSize
}

// ShardSize - returns actual shared size from erasure blockSize.
func (e ErasureInfo) ShardSize() int64 {
	return ceilFrac(e.BlockSize, int64(e.DataBlocks))
}

	}
	w := metacacheWriter{
		mw:        nil,
		blockSize: blockSize,
	}
	w.creator = func() error {
		s2w := s2.NewWriter(out, s2.WriterBlockSize(blockSize), s2.WriterConcurrency(2))
		w.mw = msgp.NewWriter(s2w)
		w.creator = nil
		if err := w.mw.WriteByte(metacacheStreamVersion); err != nil {
			return err
		}

		w.closer = func() (err error) {
			defer func() {
				cerr := s2w.Close()

	}
	if unMarshalXLMeta.Erasure.BlockSize != jsoniterXLMeta.Erasure.BlockSize {
		t.Errorf("Expected the erasure block size to be %v, but got %v.", unMarshalXLMeta.Erasure.BlockSize, jsoniterXLMeta.Erasure.BlockSize)
	}
	if unMarshalXLMeta.Erasure.Index != jsoniterXLMeta.Erasure.Index {

		case "ParityBlocks":
			z.ParityBlocks, err = dc.ReadInt()
			if err != nil {
				err = msgp.WrapError(err, "ParityBlocks")
				return
			}
		case "BlockSize":
			z.BlockSize, err = dc.ReadInt64()
			if err != nil {
				err = msgp.WrapError(err, "BlockSize")
				return
			}
		case "Index":
			z.Index, err = dc.ReadInt()
			if err != nil {
				err = msgp.WrapError(err, "Index")
				return
			}

		// max requests per node is calculated as
		// total_ram / ram_per_request
		blockSize := xioutil.LargeBlock + xioutil.SmallBlock
		if legacy {
			// ram_per_request is (1MiB+32KiB) * driveCount \
			//    + 2 * 10MiB (default erasure block size v1) + 2 * 1MiB (default erasure block size v2)
			apiRequestsMaxPerNode = int(maxMem / uint64(maxSetDrives*blockSize+int(blockSizeV1*2+blockSizeV2*2)))
		} else {

		Size:             0,
		Mode:             0,
		Metadata:         nil,
		Parts:            nil,
		Erasure: ErasureInfo{
			Algorithm:    ReedSolomon.String(),
			DataBlocks:   4,
			ParityBlocks: 2,
			BlockSize:    10000,
			Index:        1,
			Distribution: []int{1, 2, 3, 4, 5, 6, 7, 8},
			Checksums: []ChecksumInfo{{
				PartNumber: 1,
				Algorithm:  HighwayHash256S,
				Hash:       nil,
			}},
		},

				Index:      []uint8(nil),
				Checksums:  map[string]string(nil),
			},
		},
		Erasure: ErasureInfo{
			Algorithm:    "ReedSolomon",
			DataBlocks:   6,
			ParityBlocks: 6,
			BlockSize:    1048576,
			Index:        1,
			Distribution: []int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12},
			Checksums:    []ChecksumInfo{{PartNumber: 1, Algorithm: 0x3, Hash: []uint8{}}},
		},
		NumVersions: 1,

	queryVals := make(url.Values)
	if opts.Serial {
		queryVals.Set("serial", "true")
	}
	queryVals.Set("blocksize", strconv.FormatUint(opts.BlockSize, 10))
	queryVals.Set("filesize", strconv.FormatUint(opts.FileSize, 10))

	respBody, err := client.callWithContext(ctx, peerRESTMethodDriveSpeedTest, queryVals, nil, -1)
	if err != nil {

// offsets and lengths that are multiples of blockSize.
func alignSparseEntries(src []sparseEntry, size int64) []sparseEntry {
	dst := src[:0]
	for _, s := range src {
		pos, end := s.Offset, s.endOffset()
		pos += blockPadding(+pos) // Round-up to nearest blockSize
		if end != size {
			end -= blockPadding(-end) // Round-down to nearest blockSize
		}
		if pos < end {