VictoriaMetrics/lib/logstorage/u128.go
Aliaksandr Valialkin f86e093b20
lib/logstorage: improve performance for streamID.marshalString() by more than 2x
The streamID.marshalString() is executed in hot path if the query selects _stream_id field.

Command to run the benchmark:

go test ./lib/logstorage/ -run=NONE -bench=BenchmarkStreamIDMarshalString -benchtime=5s

Results before the commit:

BenchmarkStreamIDMarshalString-16    	438480714	        14.04 ns/op	  71.23 MB/s	       0 B/op	       0 allocs/op

Results after the commit:

BenchmarkStreamIDMarshalString-16    	982459660	         6.049 ns/op	 165.30 MB/s	       0 B/op	       0 allocs/op
2024-09-24 18:35:04 +02:00

75 lines
1.9 KiB
Go

package logstorage
import (
"fmt"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/encoding"
)
// u128 is 128-bit uint number.
//
// It is used as an unique id of stream.
type u128 struct {
hi uint64
lo uint64
}
// String returns human-readable representation of u.
func (u *u128) String() string {
return fmt.Sprintf("{hi=%d,lo=%d}", u.hi, u.lo)
}
// less returns true if u is less than a.
func (u *u128) less(a *u128) bool {
if u.hi != a.hi {
return u.hi < a.hi
}
return u.lo < a.lo
}
// equal returns true if u equalst to a.
func (u *u128) equal(a *u128) bool {
return u.hi == a.hi && u.lo == a.lo
}
func (u *u128) marshalString(dst []byte) []byte {
dst = marshalUint64Hex(dst, u.hi)
dst = marshalUint64Hex(dst, u.lo)
return dst
}
func marshalUint64Hex(dst []byte, n uint64) []byte {
dst = marshalByteHex(dst, byte(n>>56))
dst = marshalByteHex(dst, byte(n>>48))
dst = marshalByteHex(dst, byte(n>>40))
dst = marshalByteHex(dst, byte(n>>32))
dst = marshalByteHex(dst, byte(n>>24))
dst = marshalByteHex(dst, byte(n>>16))
dst = marshalByteHex(dst, byte(n>>8))
dst = marshalByteHex(dst, byte(n))
return dst
}
func marshalByteHex(dst []byte, x byte) []byte {
return append(dst, hexByteMap[(x>>4)&15], hexByteMap[x&15])
}
var hexByteMap = [16]byte{'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'}
// marshal appends the marshaled u to dst and returns the result.
func (u *u128) marshal(dst []byte) []byte {
dst = encoding.MarshalUint64(dst, u.hi)
dst = encoding.MarshalUint64(dst, u.lo)
return dst
}
// unmarshal unmarshals u from src and returns the tail.
func (u *u128) unmarshal(src []byte) ([]byte, error) {
if len(src) < 16 {
return src, fmt.Errorf("cannot unmarshal u128 from %d bytes; need at least 16 bytes", len(src))
}
u.hi = encoding.UnmarshalUint64(src[:8])
u.lo = encoding.UnmarshalUint64(src[8:])
return src[16:], nil
}