测试 map 的 assign 性能

gistfile1.txt

goos: darwin
goarch: amd64
pkg: perf
BenchmarkMapAssign
BenchmarkMapAssign/struct{}
BenchmarkMapAssign/struct{}-4         	  342277	      3384 ns/op	    1658 B/op	       7 allocs/op
BenchmarkMapAssign/struct{}#01
BenchmarkMapAssign/struct{}#01-4      	  176937	      6258 ns/op	    3071 B/op	      17 allocs/op
BenchmarkMapAssign/bool
BenchmarkMapAssign/bool-4             	  377792	      3118 ns/op	    3109 B/op	       2 allocs/op
BenchmarkMapAssign/bool#01
BenchmarkMapAssign/bool#01-4          	  329834	      3270 ns/op	    1815 B/op	       7 allocs/op
BenchmarkMapAssign/bool#02
BenchmarkMapAssign/bool#02-4          	  177361	      6254 ns/op	    3380 B/op	      17 allocs/op
PASS

map_test.go

package main

import (
	"testing"
)

func BenchmarkMapAssign(b *testing.B) {
	const max = 100
	b.Run("struct{}", func(b *testing.B) {
		b.ReportAllocs()
		for i := 0; i < b.N; i++ {
			dupDocs := make(map[int]struct{},max*4/4)
			for i := 0; i < max; i++ {
				dupDocs[i]= struct{}{}
			}
		}
	})
	b.Run("struct{}", func(b *testing.B) {
		b.ReportAllocs()
		for i := 0; i < b.N; i++ {
			dupDocs := make(map[int]struct{},0)
			for i := 0; i < max; i++ {
				dupDocs[i]= struct{}{}
			}
		}
	})
	b.Run("bool", func(b *testing.B) {
		b.ReportAllocs()
		for i := 0; i < b.N; i++ {
			dupDocs := make(map[int]byte,max*4/2)
			for i := 0; i < max; i++ {
				dupDocs[i]= 1
			}
		}
	})
	b.Run("bool", func(b *testing.B) {
		b.ReportAllocs()
		for i := 0; i < b.N; i++ {
			dupDocs := make(map[int]byte,max*4/4)
			for i := 0; i < max; i++ {
				dupDocs[i]= 1
			}
		}
	})
	b.Run("bool", func(b *testing.B) {
		b.ReportAllocs()
		for i := 0; i < b.N; i++ {
			dupDocs := make(map[int]byte)
			for i := 0; i < max; i++ {
				dupDocs[i]= 1
			}
		}
	})
}