VictoriaMetrics/lib/logstorage/values_encoder.go
2023-06-19 22:55:12 -07:00

743 lines
18 KiB
Go

package logstorage
import (
"fmt"
"math"
"math/bits"
"strconv"
"strings"
"sync"
"time"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/encoding"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
)
// valueType is the type of values stored in every column block.
type valueType byte
const (
// valueTypeUnknown is used for determining whether the value type is unknown.
valueTypeUnknown = valueType(0)
// default encoding for column blocks. Strings are stored as is.
valueTypeString = valueType(1)
// column blocks with small number of unique values are encoded as dict.
valueTypeDict = valueType(2)
// uint values up to 2^8-1 are encoded into valueTypeUint8.
// Every value occupies a single byte.
valueTypeUint8 = valueType(3)
// uint values up to 2^16-1 are encoded into valueTypeUint16.
// Every value occupies 2 bytes.
valueTypeUint16 = valueType(4)
// uint values up to 2^31-1 are encoded into valueTypeUint32.
// Every value occupies 4 bytes.
valueTypeUint32 = valueType(5)
// uint values up to 2^64-1 are encoded into valueTypeUint64.
// Every value occupies 8 bytes.
valueTypeUint64 = valueType(6)
// floating-point values are encoded into valueTypeFloat64.
valueTypeFloat64 = valueType(7)
// column blocks with ipv4 addresses are encoded as 4-byte strings.
valueTypeIPv4 = valueType(8)
// column blocks with ISO8601 timestamps are encoded into valueTypeTimestampISO8601.
// These timestamps are commonly used by Logstash.
valueTypeTimestampISO8601 = valueType(9)
)
type valuesEncoder struct {
// buf contains data for values.
buf []byte
// values contains encoded values.
values []string
}
func (ve *valuesEncoder) reset() {
ve.buf = ve.buf[:0]
vs := ve.values
for i := range vs {
vs[i] = ""
}
ve.values = vs[:0]
}
// encode encodes values to ve.values and returns the encoded value type with min/max encoded values.
func (ve *valuesEncoder) encode(values []string, dict *valuesDict) (valueType, uint64, uint64) {
ve.reset()
if len(values) == 0 {
return valueTypeString, 0, 0
}
var vt valueType
var minValue, maxValue uint64
// Try dict encoding at first, since it gives the highest speedup during querying.
// It also usually gives the best compression, since every value is encoded as a single byte.
ve.buf, ve.values, vt = tryDictEncoding(ve.buf[:0], ve.values[:0], values, dict)
if vt != valueTypeUnknown {
return vt, 0, 0
}
ve.buf, ve.values, vt, minValue, maxValue = tryUintEncoding(ve.buf[:0], ve.values[:0], values)
if vt != valueTypeUnknown {
return vt, minValue, maxValue
}
ve.buf, ve.values, vt, minValue, maxValue = tryFloat64Encoding(ve.buf[:0], ve.values[:0], values)
if vt != valueTypeUnknown {
return vt, minValue, maxValue
}
ve.buf, ve.values, vt, minValue, maxValue = tryIPv4Encoding(ve.buf[:0], ve.values[:0], values)
if vt != valueTypeUnknown {
return vt, minValue, maxValue
}
ve.buf, ve.values, vt, minValue, maxValue = tryTimestampISO8601Encoding(ve.buf[:0], ve.values[:0], values)
if vt != valueTypeUnknown {
return vt, minValue, maxValue
}
// Fall back to default encoding, e.g. leave values as is.
ve.values = append(ve.values[:0], values...)
return valueTypeString, 0, 0
}
func getValuesEncoder() *valuesEncoder {
v := valuesEncoderPool.Get()
if v == nil {
return &valuesEncoder{}
}
return v.(*valuesEncoder)
}
func putValuesEncoder(ve *valuesEncoder) {
ve.reset()
valuesEncoderPool.Put(ve)
}
var valuesEncoderPool sync.Pool
type valuesDecoder struct {
buf []byte
}
func (vd *valuesDecoder) reset() {
vd.buf = vd.buf[:0]
}
// decodeInplace decodes values encoded with the given vt and the given dict inplace.
//
// the decoded values remain valid until vd.reset() is called.
func (vd *valuesDecoder) decodeInplace(values []string, vt valueType, dict *valuesDict) error {
// do not reset vd.buf, since it may contain previously decoded data,
// which must be preserved until reset() call.
dstBuf := vd.buf
switch vt {
case valueTypeString:
// nothing to do - values are already decoded.
case valueTypeUint8:
for i, v := range values {
if len(v) != 1 {
return fmt.Errorf("unexpected value length for uint8; got %d; want 1", len(v))
}
n := uint64(v[0])
dstLen := len(dstBuf)
dstBuf = strconv.AppendUint(dstBuf, n, 10)
values[i] = bytesutil.ToUnsafeString(dstBuf[dstLen:])
}
case valueTypeUint16:
for i, v := range values {
if len(v) != 2 {
return fmt.Errorf("unexpected value length for uint16; got %d; want 2", len(v))
}
b := bytesutil.ToUnsafeBytes(v)
n := uint64(encoding.UnmarshalUint16(b))
dstLen := len(dstBuf)
dstBuf = strconv.AppendUint(dstBuf, n, 10)
values[i] = bytesutil.ToUnsafeString(dstBuf[dstLen:])
}
case valueTypeUint32:
for i, v := range values {
if len(v) != 4 {
return fmt.Errorf("unexpected value length for uint32; got %d; want 4", len(v))
}
b := bytesutil.ToUnsafeBytes(v)
n := uint64(encoding.UnmarshalUint32(b))
dstLen := len(dstBuf)
dstBuf = strconv.AppendUint(dstBuf, n, 10)
values[i] = bytesutil.ToUnsafeString(dstBuf[dstLen:])
}
case valueTypeUint64:
for i, v := range values {
if len(v) != 8 {
return fmt.Errorf("unexpected value length for uint64; got %d; want 8", len(v))
}
b := bytesutil.ToUnsafeBytes(v)
n := encoding.UnmarshalUint64(b)
dstLen := len(dstBuf)
dstBuf = strconv.AppendUint(dstBuf, n, 10)
values[i] = bytesutil.ToUnsafeString(dstBuf[dstLen:])
}
case valueTypeDict:
dictValues := dict.values
for i, v := range values {
id := int(v[0])
if id >= len(dictValues) {
return fmt.Errorf("unexpected dictionary id: %d; it must be smaller than %d", id, len(dictValues))
}
values[i] = dictValues[id]
}
case valueTypeIPv4:
for i, v := range values {
if len(v) != 4 {
return fmt.Errorf("unexpected value length for ipv4; got %d; want 4", len(v))
}
dstLen := len(dstBuf)
dstBuf = toIPv4String(dstBuf, v)
values[i] = bytesutil.ToUnsafeString(dstBuf[dstLen:])
}
case valueTypeTimestampISO8601:
for i, v := range values {
if len(v) != 8 {
return fmt.Errorf("unexpected value length for uint64; got %d; want 8", len(v))
}
dstLen := len(dstBuf)
dstBuf = toTimestampISO8601String(dstBuf, v)
values[i] = bytesutil.ToUnsafeString(dstBuf[dstLen:])
}
case valueTypeFloat64:
for i, v := range values {
if len(v) != 8 {
return fmt.Errorf("unexpected value length for uint64; got %d; want 8", len(v))
}
dstLen := len(dstBuf)
dstBuf = toFloat64String(dstBuf, v)
values[i] = bytesutil.ToUnsafeString(dstBuf[dstLen:])
}
default:
return fmt.Errorf("unknown valueType=%d", vt)
}
vd.buf = dstBuf
return nil
}
func toTimestampISO8601String(dst []byte, v string) []byte {
b := bytesutil.ToUnsafeBytes(v)
n := encoding.UnmarshalUint64(b)
t := time.Unix(0, int64(n)).UTC()
dst = t.AppendFormat(dst, iso8601Timestamp)
return dst
}
func toIPv4String(dst []byte, v string) []byte {
dst = strconv.AppendUint(dst, uint64(v[0]), 10)
dst = append(dst, '.')
dst = strconv.AppendUint(dst, uint64(v[1]), 10)
dst = append(dst, '.')
dst = strconv.AppendUint(dst, uint64(v[2]), 10)
dst = append(dst, '.')
dst = strconv.AppendUint(dst, uint64(v[3]), 10)
return dst
}
func toFloat64String(dst []byte, v string) []byte {
b := bytesutil.ToUnsafeBytes(v)
n := encoding.UnmarshalUint64(b)
f := math.Float64frombits(n)
dst = strconv.AppendFloat(dst, f, 'g', -1, 64)
return dst
}
func getValuesDecoder() *valuesDecoder {
v := valuesDecoderPool.Get()
if v == nil {
return &valuesDecoder{}
}
return v.(*valuesDecoder)
}
func putValuesDecoder(vd *valuesDecoder) {
vd.reset()
valuesDecoderPool.Put(vd)
}
var valuesDecoderPool sync.Pool
func tryTimestampISO8601Encoding(dstBuf []byte, dstValues, srcValues []string) ([]byte, []string, valueType, uint64, uint64) {
u64s := encoding.GetUint64s(len(srcValues))
defer encoding.PutUint64s(u64s)
a := u64s.A
var minValue, maxValue uint64
for i, v := range srcValues {
n, ok := tryParseTimestampISO8601(v)
if !ok {
return dstBuf, dstValues, valueTypeUnknown, 0, 0
}
a[i] = n
if i == 0 || n < minValue {
minValue = n
}
if i == 0 || n > maxValue {
maxValue = n
}
}
for _, n := range a {
dstLen := len(dstBuf)
dstBuf = encoding.MarshalUint64(dstBuf, n)
v := bytesutil.ToUnsafeString(dstBuf[dstLen:])
dstValues = append(dstValues, v)
}
return dstBuf, dstValues, valueTypeTimestampISO8601, minValue, maxValue
}
func tryParseTimestampISO8601(s string) (uint64, bool) {
// Do not parse timestamps with timezone, since they cannot be converted back
// to the same string representation in general case.
// This may break search.
if len(s) != len("2006-01-02T15:04:05.000Z") {
return 0, false
}
// Parse year
if s[len("YYYY")] != '-' {
return 0, false
}
yearStr := s[:len("YYYY")]
n, ok := tryParseUint64(yearStr)
if !ok || n > 3000 {
return 0, false
}
year := int(n)
s = s[len("YYYY")+1:]
// Parse month
if s[len("MM")] != '-' {
return 0, false
}
monthStr := s[:len("MM")]
n, ok = tryParseUint64(monthStr)
if !ok || n < 1 || n > 12 {
return 0, false
}
month := time.Month(n)
s = s[len("MM")+1:]
// Parse day
if s[len("DD")] != 'T' {
return 0, false
}
dayStr := s[:len("DD")]
n, ok = tryParseUint64(dayStr)
if !ok || n < 1 || n > 31 {
return 0, false
}
day := int(n)
s = s[len("DD")+1:]
// Parse hour
if s[len("HH")] != ':' {
return 0, false
}
hourStr := s[:len("HH")]
n, ok = tryParseUint64(hourStr)
if !ok || n > 23 {
return 0, false
}
hour := int(n)
s = s[len("HH")+1:]
// Parse minute
if s[len("MM")] != ':' {
return 0, false
}
minuteStr := s[:len("MM")]
n, ok = tryParseUint64(minuteStr)
if !ok || n > 59 {
return 0, false
}
minute := int(n)
s = s[len("MM")+1:]
// Parse second
if s[len("SS")] != '.' {
return 0, false
}
secondStr := s[:len("SS")]
n, ok = tryParseUint64(secondStr)
if !ok || n > 59 {
return 0, false
}
second := int(n)
s = s[len("SS")+1:]
// Parse millisecond
tzDelimiter := s[len("000")]
if tzDelimiter != 'Z' {
return 0, false
}
millisecondStr := s[:len("000")]
n, ok = tryParseUint64(millisecondStr)
if !ok || n > 999 {
return 0, false
}
millisecond := int(n)
s = s[len("000")+1:]
if len(s) != 0 {
return 0, false
}
t := time.Date(year, month, day, hour, minute, second, millisecond*1e6, time.UTC)
ts := t.UnixNano()
return uint64(ts), true
}
func tryParseUint64(s string) (uint64, bool) {
if len(s) == 0 || len(s) > 18 {
return 0, false
}
n := uint64(0)
for i := 0; i < len(s); i++ {
ch := s[i]
if ch < '0' || ch > '9' {
return 0, false
}
n *= 10
n += uint64(ch - '0')
}
return n, true
}
const iso8601Timestamp = "2006-01-02T15:04:05.000Z"
func tryIPv4Encoding(dstBuf []byte, dstValues, srcValues []string) ([]byte, []string, valueType, uint64, uint64) {
u32s := encoding.GetUint32s(len(srcValues))
defer encoding.PutUint32s(u32s)
a := u32s.A
var minValue, maxValue uint32
for i, v := range srcValues {
n, ok := tryParseIPv4(v)
if !ok {
return dstBuf, dstValues, valueTypeUnknown, 0, 0
}
a[i] = n
if i == 0 || n < minValue {
minValue = n
}
if i == 0 || n > maxValue {
maxValue = n
}
}
for _, n := range a {
dstLen := len(dstBuf)
dstBuf = encoding.MarshalUint32(dstBuf, n)
v := bytesutil.ToUnsafeString(dstBuf[dstLen:])
dstValues = append(dstValues, v)
}
return dstBuf, dstValues, valueTypeIPv4, uint64(minValue), uint64(maxValue)
}
func tryParseIPv4(s string) (uint32, bool) {
if len(s) < len("1.1.1.1") || len(s) > len("255.255.255.255") || strings.Count(s, ".") != 3 {
// Fast path - the entry isn't IPv4
return 0, false
}
var octets [4]byte
var v uint64
var ok bool
// Parse octet 1
n := strings.IndexByte(s, '.')
if n <= 0 || n > 3 {
return 0, false
}
v, ok = tryParseUint64(s[:n])
if !ok || v > 255 {
return 0, false
}
octets[0] = byte(v)
s = s[n+1:]
// Parse octet 2
n = strings.IndexByte(s, '.')
if n <= 0 || n > 3 {
return 0, false
}
v, ok = tryParseUint64(s[:n])
if !ok || v > 255 {
return 0, false
}
octets[1] = byte(v)
s = s[n+1:]
// Parse octet 3
n = strings.IndexByte(s, '.')
if n <= 0 || n > 3 {
return 0, false
}
v, ok = tryParseUint64(s[:n])
if !ok || v > 255 {
return 0, false
}
octets[2] = byte(v)
s = s[n+1:]
// Parse octet 4
v, ok = tryParseUint64(s)
if !ok || v > 255 {
return 0, false
}
octets[3] = byte(v)
ipv4 := encoding.UnmarshalUint32(octets[:])
return ipv4, true
}
func tryFloat64Encoding(dstBuf []byte, dstValues, srcValues []string) ([]byte, []string, valueType, uint64, uint64) {
u64s := encoding.GetUint64s(len(srcValues))
defer encoding.PutUint64s(u64s)
a := u64s.A
var minValue, maxValue float64
for i, v := range srcValues {
f, ok := tryParseFloat64(v)
if !ok {
return dstBuf, dstValues, valueTypeUnknown, 0, 0
}
a[i] = math.Float64bits(f)
if i == 0 || f < minValue {
minValue = f
}
if i == 0 || f > maxValue {
maxValue = f
}
}
for _, n := range a {
dstLen := len(dstBuf)
dstBuf = encoding.MarshalUint64(dstBuf, n)
v := bytesutil.ToUnsafeString(dstBuf[dstLen:])
dstValues = append(dstValues, v)
}
minValueU64 := math.Float64bits(minValue)
maxValueU64 := math.Float64bits(maxValue)
return dstBuf, dstValues, valueTypeFloat64, minValueU64, maxValueU64
}
func tryParseFloat64(s string) (float64, bool) {
if len(s) == 0 || len(s) > 20 {
return 0, false
}
// Allow only decimal digits, minus and a dot.
// Do not allows scientific notation (for example 1.23E+05),
// since it cannot be converted back to the same string form.
minus := s[0] == '-'
if minus {
s = s[1:]
}
n := strings.IndexByte(s, '.')
if n < 0 {
// fast path - there are no dots
n, ok := tryParseUint64(s)
if !ok {
return 0, false
}
f := float64(n)
if minus {
f = -f
}
return f, true
}
if n == 0 || n == len(s)-1 {
// Do not allow dots at the beginning and at the end of s,
// since they cannot be converted back to the same string form.
return 0, false
}
sInt := s[:n]
sFrac := s[n+1:]
nInt, ok := tryParseUint64(sInt)
if !ok {
return 0, false
}
nFrac, ok := tryParseUint64(sFrac)
if !ok {
return 0, false
}
f := math.FMA(float64(nFrac), math.Pow10(-len(sFrac)), float64(nInt))
if minus {
f = -f
}
return f, true
}
func tryUintEncoding(dstBuf []byte, dstValues, srcValues []string) ([]byte, []string, valueType, uint64, uint64) {
u64s := encoding.GetUint64s(len(srcValues))
defer encoding.PutUint64s(u64s)
a := u64s.A
var minValue, maxValue uint64
for i, v := range srcValues {
n, ok := tryParseUint64(v)
if !ok {
return dstBuf, dstValues, valueTypeUnknown, 0, 0
}
a[i] = n
if i == 0 || n < minValue {
minValue = n
}
if i == 0 || n > maxValue {
maxValue = n
}
}
minBitSize := bits.Len64(maxValue)
if minBitSize <= 8 {
for _, n := range a {
dstLen := len(dstBuf)
dstBuf = append(dstBuf, byte(n))
v := bytesutil.ToUnsafeString(dstBuf[dstLen:])
dstValues = append(dstValues, v)
}
return dstBuf, dstValues, valueTypeUint8, minValue, maxValue
}
if minBitSize <= 16 {
for _, n := range a {
dstLen := len(dstBuf)
dstBuf = encoding.MarshalUint16(dstBuf, uint16(n))
v := bytesutil.ToUnsafeString(dstBuf[dstLen:])
dstValues = append(dstValues, v)
}
return dstBuf, dstValues, valueTypeUint16, minValue, maxValue
}
if minBitSize <= 32 {
for _, n := range a {
dstLen := len(dstBuf)
dstBuf = encoding.MarshalUint32(dstBuf, uint32(n))
v := bytesutil.ToUnsafeString(dstBuf[dstLen:])
dstValues = append(dstValues, v)
}
return dstBuf, dstValues, valueTypeUint32, minValue, maxValue
}
for _, n := range a {
dstLen := len(dstBuf)
dstBuf = encoding.MarshalUint64(dstBuf, n)
v := bytesutil.ToUnsafeString(dstBuf[dstLen:])
dstValues = append(dstValues, v)
}
return dstBuf, dstValues, valueTypeUint64, minValue, maxValue
}
func tryDictEncoding(dstBuf []byte, dstValues, srcValues []string, dict *valuesDict) ([]byte, []string, valueType) {
dict.reset()
dstBufOrig := dstBuf
dstValuesOrig := dstValues
for _, v := range srcValues {
id, ok := dict.getOrAdd(v)
if !ok {
dict.reset()
return dstBufOrig, dstValuesOrig, valueTypeUnknown
}
dstLen := len(dstBuf)
dstBuf = append(dstBuf, id)
v := bytesutil.ToUnsafeString(dstBuf[dstLen:])
dstValues = append(dstValues, v)
}
return dstBuf, dstValues, valueTypeDict
}
type valuesDict struct {
values []string
}
func (vd *valuesDict) reset() {
vs := vd.values
for i := range vs {
vs[i] = ""
}
vd.values = vs[:0]
}
func (vd *valuesDict) copyFrom(src *valuesDict) {
vd.reset()
vd.values = append(vd.values[:0], src.values...)
}
func (vd *valuesDict) getOrAdd(k string) (byte, bool) {
if len(k) > maxDictSizeBytes {
return 0, false
}
vs := vd.values
dictSizeBytes := 0
for i, v := range vs {
if k == v {
return byte(i), true
}
dictSizeBytes += len(v)
}
if len(vs) >= maxDictLen || dictSizeBytes+len(k) > maxDictSizeBytes {
return 0, false
}
vs = append(vs, k)
vd.values = vs
return byte(len(vs) - 1), true
}
func (vd *valuesDict) marshal(dst []byte) []byte {
values := vd.values
if len(values) > maxDictLen {
logger.Panicf("BUG: valuesDict may contain max %d items; got %d items", maxDictLen, len(values))
}
dst = append(dst, byte(len(values)))
for _, v := range values {
dst = encoding.MarshalBytes(dst, bytesutil.ToUnsafeBytes(v))
}
return dst
}
func (vd *valuesDict) unmarshal(src []byte) ([]byte, error) {
vd.reset()
srcOrig := src
if len(src) < 1 {
return srcOrig, fmt.Errorf("cannot umarshal dict len from 0 bytes; need at least 1 byte")
}
dictLen := int(src[0])
src = src[1:]
for i := 0; i < dictLen; i++ {
tail, data, err := encoding.UnmarshalBytes(src)
if err != nil {
return srcOrig, fmt.Errorf("cannot umarshal value %d out of %d from dict: %w", i, dictLen, err)
}
src = tail
// Do not use bytesutil.InternBytes(data) here, since it works slower than the string(data) in prod
v := string(data)
vd.values = append(vd.values, v)
}
return src, nil
}
// maxDictSizeBytes is the maximum length of all the keys in the valuesDict
const maxDictSizeBytes = 256
// maxDictLen is the maximum number of entries in the valuesDict.
//
// it shouldn't exceed 255, since the dict len is marshaled into a single byte.
const maxDictLen = 8