type Metrics struct {
	ReqOK   uint64                   `json:"kms_req_success"` // Number of requests that succeeded
	ReqErr  uint64                   `json:"kms_req_error"`   // Number of requests that failed with a defined error
	ReqFail uint64                   `json:"kms_req_failure"` // Number of requests that failed with an undefined error
	Latency map[time.Duration]uint64 `json:"kms_resp_time"`   // Latency histogram of all requests

}

// SizeTooSmall reader size too small
type SizeTooSmall struct {
	Want int64
	Got  int64
}

func (e SizeTooSmall) Error() string {
	return fmt.Sprintf("Size small: got %d, want %d", e.Got, e.Want)
}

// SizeTooLarge reader size too large
type SizeTooLarge struct {
	Want int64
	Got  int64
}

func (e SizeTooLarge) Error() string {

	return &streamingBitrotWriter{iow: ioutil.NopCloser(w), h: algo.New(), shardSize: shardSize, canClose: nil, closeWithErr: func(err error) {}}
}

// Returns streaming bitrot writer implementation.
func newStreamingBitrotWriter(disk StorageAPI, origvolume, volume, filePath string, length int64, algo BitrotAlgorithm, shardSize int64) io.Writer {
	h := algo.New()

	bts := make([]byte, 0, v.Msgsize())
	bts, _ = v.MarshalMsg(bts[0:0])
	b.SetBytes(int64(len(bts)))
	b.ReportAllocs()
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		bts, _ = v.MarshalMsg(bts[0:0])
	}
}

func BenchmarkUnmarshalBaseOptions(b *testing.B) {
	v := BaseOptions{}
	bts, _ := v.MarshalMsg(nil)
	b.ReportAllocs()
	b.SetBytes(int64(len(bts)))
	b.ResetTimer()
	for i := 0; i < b.N; i++ {

func (ct ColumnType) Length() (length int64, ok bool) {
	if ct.LengthValue.Valid {
		return ct.LengthValue.Int64, true
	}
	return ct.SQLColumnType.Length()
}

// DecimalSize returns the scale and precision of a decimal type.
func (ct ColumnType) DecimalSize() (precision int64, scale int64, ok bool) {
	if ct.DecimalSizeValue.Valid {
		return ct.DecimalSizeValue.Int64, ct.ScaleValue.Int64, true
	}

	bts := make([]byte, 0, v.Msgsize())
	bts, _ = v.MarshalMsg(bts[0:0])
	b.SetBytes(int64(len(bts)))
	b.ReportAllocs()
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		bts, _ = v.MarshalMsg(bts[0:0])
	}
}

func BenchmarkUnmarshalActiveWorkerStat(b *testing.B) {
	v := ActiveWorkerStat{}
	bts, _ := v.MarshalMsg(nil)
	b.ReportAllocs()
	b.SetBytes(int64(len(bts)))
	b.ResetTimer()
	for i := 0; i < b.N; i++ {

	bts, _ = v.MarshalMsg(bts[0:0])
	b.SetBytes(int64(len(bts)))
	b.ReportAllocs()
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		bts, _ = v.MarshalMsg(bts[0:0])
	}
}

func BenchmarkUnmarshalBucketReplicationResyncStatus(b *testing.B) {
	v := BucketReplicationResyncStatus{}
	bts, _ := v.MarshalMsg(nil)
	b.ReportAllocs()
	b.SetBytes(int64(len(bts)))
	b.ResetTimer()
	for i := 0; i < b.N; i++ {

	if cardinality <= 0 {
		return -1
	}
	// use the faster version as per siphash docs
	// https://github.com/dchest/siphash#usage
	k0, k1 := binary.LittleEndian.Uint64(id[0:8]), binary.LittleEndian.Uint64(id[8:16])
	sum64 := siphash.Hash(k0, k1, []byte(key))
	return int(sum64 % uint64(cardinality))
}

// hashOrder - hashes input key to return consistent
// hashed integer slice. Returned integer order is salted

	bts, _ = v.MarshalMsg(bts[0:0])
	b.SetBytes(int64(len(bts)))
	b.ReportAllocs()
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		bts, _ = v.MarshalMsg(bts[0:0])
	}
}

func BenchmarkUnmarshalBucketReplicationStat(b *testing.B) {
	v := BucketReplicationStat{}
	bts, _ := v.MarshalMsg(nil)
	b.ReportAllocs()
	b.SetBytes(int64(len(bts)))
	b.ResetTimer()
	for i := 0; i < b.N; i++ {

	denom = big.NewInt(1)
	ten   = big.NewInt(10)
)

func extractDigit() int64 {
	if big.CmpInt(numer, accum) > 0 {
		return -1
	}
	tmp1.Lsh(numer, 1).Add(tmp1, numer).Add(tmp1, accum)
	big.DivModInt(tmp1, tmp2, tmp1, denom)
	tmp2.Add(tmp2, numer)
	if big.CmpInt(tmp2, denom) >= 0 {
		return -1
	}
	return tmp1.Int64()
}

func nextTerm(k int64) {
	y2 := k*2 + 1
	accum.Add(accum, tmp1.Lsh(numer, 1))