signal profiling

gistfile1.go

package main

import "fmt"
import "syscall"
import "os"
import "os/signal"
import "time"
import "runtime/pprof"

func main() {
	messages := make(chan string)

	// consumer
	go func() {
		for {
			select {
			case m := <-messages:
				fmt.Println(m)
			}
		}
	}()

	// producer
	go func() {
		for {
			time.Sleep(1 * time.Second)
			messages <- `ping`
		}
	}()

	go profile()

	// block indefinately
	select {}
}

func profile() {
	c := make(chan os.Signal, 10)
	signal.Notify(c, syscall.SIGUSR1, syscall.SIGUSR2)
	fmt.Println("waiting for SIGUSR1/SIGUSR2")

	for {
		s := <-c
		switch s {
		case syscall.SIGUSR1:
			pprof.Lookup("goroutine").WriteTo(os.Stdout, 1)
		case syscall.SIGUSR2:
			pprof.Lookup("heap").WriteTo(os.Stdout, 1)
			pprof.Lookup("block").WriteTo(os.Stdout, 1)
		}
	}
}