Concat benchmark

concat_test.go

package concat

import (
	"fmt"
	"strconv"
	"strings"
	"testing"
)

func concatFmt(a, b uint64) string {
	return fmt.Sprintf("%d@%d", a, b)
}

func concatPlus(a, b uint64) string {
	const base = 10
	return strconv.FormatUint(a, base) + "@" + strconv.FormatUint(b, base)
}

func concatSB(a, b uint64) string {
	const base = 10
	var sb strings.Builder
	sb.WriteString(strconv.FormatUint(a, base))
	sb.WriteByte('@')
	sb.WriteString(strconv.FormatUint(b, base))
	return sb.String()
}

func BenchmarkConcat(b *testing.B) {
	type testCase struct {
		name string
		a, b uint64
	}
	tcs := []testCase{
		{"zeros", 0, 0},
		{"small-big", 123, 9120497109247123},
		{"big-small", 9120497109247123, 123},
		{"big-big", 9120497109247123, 9120497109247123},
	}
	b.Run("concatFmt", func (b *testing.B) {
		for _, tc := range tcs {
			b.Run(tc.name, func (b *testing.B) {
				for i := 0; i < b.N; i++ {
					_ = concatFmt(tc.a, tc.b)
				}
			})
		}
	})
	b.Run("concatPlus", func (b *testing.B) {
		for _, tc := range tcs {
			b.Run(tc.name, func (b *testing.B) {
				for i := 0; i < b.N; i++ {
					_ = concatPlus(tc.a, tc.b)
				}
			})
		}
	})
	b.Run("concatSB", func (b *testing.B) {
		for _, tc := range tcs {
			b.Run(tc.name, func (b *testing.B) {
				for i := 0; i < b.N; i++ {
					_ = concatSB(tc.a, tc.b)
				}
			})
		}
	})
}

results.txt

➜ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: goplay/concat
cpu: Apple M1 Pro
BenchmarkConcat/concatFmt/zeros-10      19883263                60.31 ns/op            3 B/op          1 allocs/op
BenchmarkConcat/concatFmt/small-big-10          13212832                90.80 ns/op           32 B/op          2 allocs/op
BenchmarkConcat/concatFmt/big-small-10          13258746                90.19 ns/op           32 B/op          2 allocs/op
BenchmarkConcat/concatFmt/big-big-10            11662374               102.7 ns/op            64 B/op          3 allocs/op
BenchmarkConcat/concatPlus/zeros-10             46471173                25.29 ns/op            3 B/op          1 allocs/op
BenchmarkConcat/concatPlus/small-big-10         17164700                68.82 ns/op           43 B/op          3 allocs/op
BenchmarkConcat/concatPlus/big-small-10         17233651                68.93 ns/op           43 B/op          3 allocs/op
BenchmarkConcat/concatPlus/big-big-10           15554778                76.36 ns/op           80 B/op          3 allocs/op
BenchmarkConcat/concatSB/zeros-10               52523403                21.87 ns/op            8 B/op          1 allocs/op
BenchmarkConcat/concatSB/small-big-10           15188575                79.08 ns/op           56 B/op          4 allocs/op
BenchmarkConcat/concatSB/big-small-10           14948676                80.04 ns/op           67 B/op          4 allocs/op
BenchmarkConcat/concatSB/big-big-10             11224966               107.1 ns/op           144 B/op          5 allocs/op
PASS
ok      goplay/concat   16.240s