4.3 benchmark

1. Usage

• bench.go

  func Fib(n int) int {
  	if n < 2 {
  		return n
  	}
  	return Fib(n-1) + Fib(n-2)
  }

• bench_test.go

  import (
  	"testing"
  )
  
  func BenchmarkFib(b *testing.B) {
  	// run the Fib function b.N times
  	for n := 0; n < b.N; n++ {
  		Fib(10)
  	}
  }

• Tests:

  • go test -bench=.

    $ go test -bench=.
    goos: windows
    goarch: amd64
    pkg: test/bench
    BenchmarkFib-6           3888090               307 ns/op
    PASS
    ok      test/bench      1.850s

  • View memory allocation information: go test -bench=. -benchmem

    $ go test -bench=. -benchmem
    goos: windows
    goarch: amd64
    pkg: test/bench
    BenchmarkFib-6           3897542               307 ns/op               0 B/op          0 allocs/op
    PASS
    ok      test/bench      1.858s

  • Generate CPU information: go test -bench=. -benchmem -cpuprofile prof.cpu
    • go tool pprof bench.test.exe prof.cpu
  • Generate memory information: go test -bench=. -benchmem -memprofile prof.mem
    • go tool pprof bench.test.exe prof.mem
  • Generate all information: go test -bench=".*" -benchtime=1000x -cpuprofile cpu.profile -benchmem -memprofile=mem.profile -blockprofile=block.profile -trace trace.out -mutexprofile mutex.out

2. Interpreting Results

Interpreting Go Benchmark Results | Shuiyue Huaer

3. References

How to write benchmarks in Go | Dave Cheney Top 10 Common Go Mistakes, Part 2: Benchmark Performance Testing Pitfalls - Juejin benchmark | High Performance Go | GeekTutu benchmarking - What does allocs/op and B/op mean in go benchmark? - Stack Overflow Interpreting Go Benchmark Results | Shuiyue Huaer Golang Performance Optimization Analysis: benchmark with pprof - Jiujian - cnblogs