// been seen recently due to hardware issues
				// causes Reads() to go slower than Writes().
				//
				// Send such results anyways as this shall
				// expose a problem underneath.
				if totalPut > throughputHighestPut {
					throughputHighestResults = results
					throughputHighestPut = totalPut
					// let the client see lower value as well
					throughputHighestGet = totalGet
				}
				sendResult()

// preferredKexAlgos specifies the default preference for key-exchange
// algorithms in preference order. The diffie-hellman-group16-sha512 algorithm
// is disabled by default because it is a bit slower than the others.
var preferredKexAlgos = []string{
	kexAlgoCurve25519SHA256, kexAlgoCurve25519SHA256LibSSH,
	kexAlgoECDH256, kexAlgoECDH384, kexAlgoECDH521,
	kexAlgoDH14SHA256, kexAlgoDH14SHA1,
}

// their upper case.
func ToUpper(s []byte) []byte {
	isASCII, hasLower := true, false
	for i := 0; i < len(s); i++ {
		c := s[i]
		if c >= utf8.RuneSelf {
			isASCII = false
			break
		}
		hasLower = hasLower || ('a' <= c && c <= 'z')
	}

	if isASCII { // optimize for ASCII-only byte slices.
		if !hasLower {
			// Just return a copy.
			return append([]byte(""), s...)
		}

// the maximum number of bytes allowed for each string field and
// the integer type used to store each numeric field
// (where timestamps are stored as the number of seconds since the Unix epoch).
//
// The table's lower portion shows specialized features of each format,
// such as supported string encodings, support for sub-second timestamps,
// or support for sparse files.
//
// The Writer currently provides no support for sparse files.

		return map[string]string{r.contentHash.Type.String(): r.trailer.Get(r.contentHash.Type.Key())}
	}
	return map[string]string{r.contentHash.Type.String(): r.contentHash.Encoded}
}

var _ io.Closer = (*Reader)(nil) // compiler check

// Close and release resources.

func (fi *FileInfo) TierFreeVersionID() string {
	return fi.Metadata[ReservedMetadataPrefixLower+tierFVID]
}

// SetTierFreeVersion sets fi as a free-version. This method is used by
// lower layers to indicate a free-version.
func (fi *FileInfo) SetTierFreeVersion() {
	if fi.Metadata == nil {
		fi.Metadata = make(map[string]string)
	}
	fi.Metadata[ReservedMetadataPrefixLower+tierFVMarker] = ""
}

	for k, vv := range req.Header {
		// If request header key is not in ignored headers, then add it.
		if _, ok := ignoredStreamingHeaders[http.CanonicalHeaderKey(k)]; !ok {
			headerMap[strings.ToLower(k)] = vv
		}
	}

	// Get header keys.
	headers := []string{"host"}
	for k := range headerMap {
		headers = append(headers, k)
	}
	sort.Strings(headers)

	// Get canonical headers.

		t.Fatal(err)
	}
	_, err = writer.Write([]byte("aaaaaaaaaa"))
	if err != nil {
		t.Fatal(err)
	}
	_, err = writer.Write([]byte("aaaaa"))
	if err != nil {
		t.Fatal(err)
	}
	if bw, ok := writer.(io.Closer); ok {
		bw.Close()
	}

	reader := newBitrotReader(disk, nil, volume, filePath, 35, bitrotAlgo, bitrotWriterSum(writer), 10)
	b := make([]byte, 10)
	if _, err = reader.ReadAt(b, 0); err != nil {
		t.Fatal(err)
	}

func closeBitrotReaders(rs []io.ReaderAt) {
	for _, r := range rs {
		if r != nil {
			if br, ok := r.(io.Closer); ok {
				br.Close()
			}
		}
	}
}

// Close all the writers.
func closeBitrotWriters(ws []io.Writer) {
	for _, w := range ws {
		if w != nil {
			if bw, ok := w.(io.Closer); ok {
				bw.Close()
			}
		}
	}
}

	OpResponse

	// OpDisconnect instructs that remote wants to disconnect
	OpDisconnect

	// OpMerged is several operations merged into one.
	OpMerged
)

const (
	// FlagCRCxxh3 indicates that, the lower 32 bits of xxhash3 of the serialized
	// message will be sent after the serialized message as little endian.
	FlagCRCxxh3 Flags = 1 << iota

	// FlagEOF the stream (either direction) is at EOF.
	FlagEOF