Benchmarking prints

printbench.go

package main

import (
        "fmt"
        "io"
        "os"
        . "testing"
)

// Run this with >/dev/null
func main() {
        fmt.Fprintln(os.Stderr, "fmt.Printf    ", Benchmark(func(b *B){ for i := 0; i < b.N; i++ { fmt.Printf(".") } }))
        fmt.Fprintln(os.Stderr, "fmt.Print     ", Benchmark(func(b *B){ for i := 0; i < b.N; i++ { fmt.Print(".") } }))
        fmt.Fprintln(os.Stderr, "io.WriteString", Benchmark(func(b *B){ for i := 0; i < b.N; i++ { io.WriteString(os.Stdout, ".") } }))
        fmt.Fprintln(os.Stderr, "os.WriteString", Benchmark(func(b *B){ for i := 0; i < b.N; i++ { os.Stdout.WriteString(".") } }))
}

xoutput

$ 6g *.go && 6l *.6 && ./6.out >/dev/null
fmt.Printf      5000000        594 ns/op
fmt.Print       2000000        836 ns/op
io.WriteString  5000000        501 ns/op
os.WriteString  5000000        442 ns/op