Golang: map vs struct loopkup benchmark

README.md

BenchmarkStruct1	50000000	        41.1 ns/op
BenchmarkMap1	50000000	        43.5 ns/op
BenchmarkStruct2	50000000	        42.8 ns/op
BenchmarkMap2	50000000	        44.4 ns/op
BenchmarkStruct3	50000000	        45.3 ns/op
BenchmarkMap3	50000000	        37.0 ns/op
BenchmarkStruct4	50000000	        42.2 ns/op
BenchmarkMap4	50000000	        37.3 ns/op

bench_test.go

package main

import "testing"

type Methods struct {
	Handle  string
	Get     string
	Post    string
	Delete  string
	Put     string
	Patch   string
	Options string
}

func New() *Methods {
	return &Methods{
		"handle string",
		"get string",
		"post string",
		"delete string",
		"put string",
		"patch string",
		"options string",
	}
}

func getCase1() []string {
	return []string{"GET", "POST", "MOVE", "DELETE", "PATCH", "HEAD", "OPTIONS", "COPY"}
}

func getCase2() []string {
	// no "PUT"
	return []string{"GET", "PUT", "MOVE", "OPTIONS", "COPY"}
}

func getCase3() []string {
	return []string{"PUT", "PATCH", "OPTIONS"}
}

func getCase4() []string {
	return []string{"DELETE", "OPTIONS"}
}

func PassString(str string) {

}

func GetMethodMap() map[string]string {
	return map[string]string {
		"HANDLE": "handle string",
		"GET": "get string",
		"POST": "post string",
		"DELETE": "delete string",
		"PUT": "put string",
		"PATCH": "patch string",
		"OPTIONS": "options string",
	}
}

func BenchmarkStruct1(b *testing.B) {
	methods := getCase1()
	methodMap := New()
	l := len(methods)
	for i := 0; i < b.N; i++ {
		var target string
		switch methods[i % l] {
		case "GET", "HEAD":
			target = methodMap.Get
		case "POST":
			target = methodMap.Post
		case "PUT":
			target = methodMap.Put
		case "DELETE":
			target = methodMap.Delete
		case "PATCH":
			target = methodMap.Patch
		case "OPTIONS":
			target = methodMap.Options
		default:
			target = methodMap.Handle
		}
		PassString(target)
	}
}

func BenchmarkMap1(b *testing.B) {
	methods := getCase1()
	methodMap := GetMethodMap()
	l := len(methods)
	for i := 0; i < b.N; i++ {
		m := methods[i % l]
		target, ok := methodMap[m]
		if !ok {
			target, _ = methodMap["HANDLE"]
		}
		PassString(target)
	}
}

func BenchmarkStruct2(b *testing.B) {
	methods := getCase2()
	methodMap := New()
	l := len(methods)
	for i := 0; i < b.N; i++ {
		var target string
		switch methods[i % l] {
		case "GET", "HEAD":
			target = methodMap.Get
		case "POST":
			target = methodMap.Post
		case "PUT":
			target = methodMap.Put
		case "DELETE":
			target = methodMap.Delete
		case "PATCH":
			target = methodMap.Patch
		case "OPTIONS":
			target = methodMap.Options
		default:
			target = methodMap.Handle
		}
		PassString(target)
	}
}

func BenchmarkMap2(b *testing.B) {
	methods := getCase2()
	methodMap := GetMethodMap()
	l := len(methods)
	for i := 0; i < b.N; i++ {
		m := methods[i % l]
		target, ok := methodMap[m]
		if !ok {
			target, _ = methodMap["HANDLE"]
		}
		PassString(target)
	}
}

func BenchmarkStruct3(b *testing.B) {
	methods := getCase3()
	methodMap := New()
	l := len(methods)
	for i := 0; i < b.N; i++ {
		var target string
		switch methods[i % l] {
		case "GET", "HEAD":
			target = methodMap.Get
		case "POST":
			target = methodMap.Post
		case "PUT":
			target = methodMap.Put
		case "DELETE":
			target = methodMap.Delete
		case "PATCH":
			target = methodMap.Patch
		case "OPTIONS":
			target = methodMap.Options
		default:
			target = methodMap.Handle
		}
		PassString(target)
	}
}

func BenchmarkMap3(b *testing.B) {
	methods := getCase3()
	methodMap := GetMethodMap()
	l := len(methods)
	for i := 0; i < b.N; i++ {
		m := methods[i % l]
		target, ok := methodMap[m]
		if !ok {
			target, _ = methodMap["HANDLE"]
		}
		PassString(target)
	}
}

func BenchmarkStruct4(b *testing.B) {
	methods := getCase4()
	methodMap := New()
	l := len(methods)
	for i := 0; i < b.N; i++ {
		var target string
		switch methods[i % l] {
		case "GET", "HEAD":
			target = methodMap.Get
		case "POST":
			target = methodMap.Post
		case "PUT":
			target = methodMap.Put
		case "DELETE":
			target = methodMap.Delete
		case "PATCH":
			target = methodMap.Patch
		case "OPTIONS":
			target = methodMap.Options
		default:
			target = methodMap.Handle
		}
		PassString(target)
	}
}

func BenchmarkMap4(b *testing.B) {
	methods := getCase4()
	methodMap := GetMethodMap()
	l := len(methods)
	for i := 0; i < b.N; i++ {
		m := methods[i % l]
		target, ok := methodMap[m]
		if !ok {
			target, _ = methodMap["HANDLE"]
		}
		PassString(target)
	}
}