mirror of
https://github.com/golang/go
synced 2024-11-06 09:16:16 -07:00
c4206d458c
We no longer use the span as the core type of tracing, instead that is an artifact of the exporter, and start and end tracing is just event based. This both makes the interface normalized, and also means the null exporter case is considerably cheaper in memory and cpu. See below for benchstat changes name old time/op new time/op delta TracingNoExporter-8 4.19µs ±12% 2.71µs ±11% -35.33% (p=0.000 n=20+20) Tracing-8 24.1µs ± 3% 5.1µs ±17% -78.66% (p=0.000 n=16+20) name old alloc/op new alloc/op delta TracingNoExporter-8 2.32kB ± 0% 0.40kB ± 0% -82.76% (p=0.000 n=20+20) Tracing-8 6.32kB ± 0% 2.32kB ± 0% -63.30% (p=0.000 n=20+20) name old allocs/op new allocs/op delta TracingNoExporter-8 35.0 ± 0% 15.0 ± 0% -57.14% (p=0.000 n=20+20) Tracing-8 215 ± 0% 35 ± 0% -83.72% (p=0.000 n=20+20) Change-Id: I3cf25871fa49584819504b5c19aa580e5dd03395 Reviewed-on: https://go-review.googlesource.com/c/tools/+/221740 Run-TryBot: Ian Cottrell <iancottrell@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
72 lines
1.4 KiB
Go
72 lines
1.4 KiB
Go
// Copyright 2019 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package export
|
|
|
|
import (
|
|
crand "crypto/rand"
|
|
"encoding/binary"
|
|
"fmt"
|
|
"math/rand"
|
|
"sync"
|
|
"sync/atomic"
|
|
)
|
|
|
|
type TraceID [16]byte
|
|
type SpanID [8]byte
|
|
|
|
func (t TraceID) String() string {
|
|
return fmt.Sprintf("%02x", t[:])
|
|
}
|
|
|
|
func (s SpanID) String() string {
|
|
return fmt.Sprintf("%02x", s[:])
|
|
}
|
|
|
|
func (s SpanID) IsValid() bool {
|
|
return s != SpanID{}
|
|
}
|
|
|
|
var (
|
|
generationMu sync.Mutex
|
|
nextSpanID uint64
|
|
spanIDInc uint64
|
|
|
|
traceIDAdd [2]uint64
|
|
traceIDRand *rand.Rand
|
|
)
|
|
|
|
func initGenerator() {
|
|
var rngSeed int64
|
|
for _, p := range []interface{}{
|
|
&rngSeed, &traceIDAdd, &nextSpanID, &spanIDInc,
|
|
} {
|
|
binary.Read(crand.Reader, binary.LittleEndian, p)
|
|
}
|
|
traceIDRand = rand.New(rand.NewSource(rngSeed))
|
|
spanIDInc |= 1
|
|
}
|
|
|
|
func newTraceID() TraceID {
|
|
generationMu.Lock()
|
|
defer generationMu.Unlock()
|
|
if traceIDRand == nil {
|
|
initGenerator()
|
|
}
|
|
var tid [16]byte
|
|
binary.LittleEndian.PutUint64(tid[0:8], traceIDRand.Uint64()+traceIDAdd[0])
|
|
binary.LittleEndian.PutUint64(tid[8:16], traceIDRand.Uint64()+traceIDAdd[1])
|
|
return tid
|
|
}
|
|
|
|
func newSpanID() SpanID {
|
|
var id uint64
|
|
for id == 0 {
|
|
id = atomic.AddUint64(&nextSpanID, spanIDInc)
|
|
}
|
|
var sid [8]byte
|
|
binary.LittleEndian.PutUint64(sid[:], id)
|
|
return sid
|
|
}
|