Benchmarklar

Test kodning to’g’riligini tekshiradi, benchmark esa uning tezligini o’lchaydi — u ham testing paketining bir qismi. Benchmark funksiyasi Benchmark bilan boshlanadi va b *testing.B argumentini oladi. Bu yerdagi eng muhim narsa — b.N: o’lchamoqchi bo’lgan kodni for i := 0; i < b.N; i++ tsikliga qo’yasiz, Go esa natija barqarorlashguncha b.N ni o’zi oshirib boraveradi. b.ReportAllocs() natijaga xotira ajratish (allocation) statistikasini ham qo’shadi.

Quyida ikkita satrni birlashtirish usulini solishtirib ko’ramiz:

concat.go


package main
 
import "strings"
 
func JoinLoop(parts []string) string {
    result := ""
    for _, p := range parts {
        result += p
    }
    return result
}
 
func JoinBuilder(parts []string) string {
    var b strings.Builder
    for _, p := range parts {
        b.WriteString(p)
    }
    return b.String()
}

concat_test.go


package main
 
import (
    "strings"
    "testing"
)
 
func BenchmarkJoinLoop(b *testing.B) {
    parts := strings.Fields(strings.Repeat("go ", 100))
    b.ReportAllocs() // xotira statistikasini yoqadi
    b.ResetTimer()   // tayyorgarlik vaqtini o'lchamaymiz
    for i := 0; i < b.N; i++ {
        JoinLoop(parts)
    }
}
 
func BenchmarkJoinBuilder(b *testing.B) {
    parts := strings.Fields(strings.Repeat("go ", 100))
    b.ReportAllocs()
    b.ResetTimer()
    for i := 0; i < b.N; i++ {
        JoinBuilder(parts)
    }
}

Benchmarklar oddiy go test da ishga tushmaydi — -bench bayrog’i kerak (argumenti regexp; hammasini yugurtirish uchun . yozing):


$ go test -bench=.
goos: linux
goarch: amd64
pkg: example/concat
cpu: 12th Gen Intel(R) Core(TM) i7-1255U
BenchmarkJoinLoop-12        173940      6820 ns/op    5400 B/op    99 allocs/op
BenchmarkJoinBuilder-12    1000000      1043 ns/op     248 B/op     5 allocs/op
PASS
ok      example/concat  3.214s

ns/op — bitta chaqiriq necha nanosekund davom etgani; B/op va allocs/op — necha bayt va necha marta xotira ajratilgani. JoinBuilder ham tezroq (6820 ga qarshi 1043 ns), ham kamroq allocation qilyapti — strings.Builder afzalligi raqamlar bilan tasdiqlandi.

Xulosa: for i := 0; i < b.N; i++ tsikli + go test -bench=.; b.ReportAllocs() (yoki -benchmem) xotira ajratish statistikasini chiqaradi.

Manba / batafsil: pkg.go.dev/testing#hdr-Benchmarks

Keyingi bo’limda kamroq tanilgan, ammo juda kuchli qurol — fuzzing ni ko’ramiz.