by-value vs. by-pointer benchmark

gistfile1.txt

package jaeger

// go test -bench=.
// BenchmarkByValue-8     	2000000000	         0.56 ns/op
// BenchmarkByPointer-8   	2000000000	         0.28 ns/op

import "testing"

func BenchmarkByValue(b *testing.B) {
	b1 := b1{}
	for n := 0; n < b.N; n++ {
		b1.setBaggage("x", "y")
	}
}

func BenchmarkByPointer(b *testing.B) {
	b2 := &b2{}
	for n := 0; n < b.N; n++ {
		b2.setBaggage("x", "y")
	}
}

type b1 struct {
	logger  Logger
	metrics *Metrics
}

func (b b1) setBaggage(k, v string) {
	b.logFields(k, v)
}

func (b b1) logFields(k, v string) {
	// no-op
}

type b2 struct {
	logger  Logger
	metrics *Metrics
}

func (b *b2) setBaggage(k, v string) {
	b.logFields(k, v)
}

func (b *b2) logFields(k, v string) {
	// no-op
}