Как ускорить код на Go с помощью закона Амдала

    "testing"
)

// go test -bench=. bench_test.go
// a = 1 / ((1 - P) + (P / S))

func calculate(parallelFactor int) {
    value := 0
    for i := 0; i < 1000000; i++ {
        value += i
    }

    wg := sync.WaitGroup{}
    wg.Add(parallelFactor)
    for i := 0; i < parallelFactor; i++ {
        go func() {
            defer wg.Done()

            localValue := 0
            for j := 0; j < 1000000/parallelFactor; j++ {
                localValue += j
            }
        }()
    }

    wg.Wait()
}

run benchmark | debug benchmark
func BenchmarkCalculation(b *testing.B) {
    parallelFactor := 1
    runtime.GOMAXPROCS(parallelFactor)
    for i := 0; i < b.N; i++ {
        calculate(parallelFactor)
    }
}

run benchmark | debug benchmark
func BenchmarkCalculation(b *testing.B) {
    parallelFactor := 2
    runtime.GOMAXPROCS(parallelFactor)
    for i := 0; i < b.N; i++ {
        calculate(parallelFactor)
    }
}