go tool pprof error

errors

$ ./malloctest --proc=2 --iters=100 --prof 2>out2.prof
$ go tool pprof malloctest out2.prof 
out2.prof: header size >= 2**16
go tool pprof: exit status 1

malloctest.go

// malloc test for false sharing

package main

import (
	"flag"
	"os"
	"runtime"
	"runtime/pprof"
	"sync"
)

var (
	procs     int
	allocsize int
	niters    int
	prof      bool
)

func init() {
	flag.IntVar(&procs, "procs", 1, "Value to set GOMAXPROCS")
	flag.IntVar(&allocsize, "size", 16, "Size of block to allocate")
	flag.IntVar(&niters, "iters", 10000, "Number of repetitions to make")
	flag.BoolVar(&prof, "proff", false, "Emit profiling data to stderr")
}

func do_thread(niters int, wg *sync.WaitGroup) {
	runtime.LockOSThread()
	for iter := 0; iter < niters; iter++ {
		b := make([]byte, allocsize)
		// Write a bunch to b.
		for i, _ := range b {
			b[i] = byte(i)
		}
		// Intentionally drop a reference to b.
		b = nil
	}
	wg.Done()
	runtime.UnlockOSThread()
}

func main() {
	flag.Parse()

	runtime.GC() // clean up garbage from init
	runtime.GOMAXPROCS(procs)

	if prof {
		pprof.StartCPUProfile(os.Stderr)
	}

	var wg sync.WaitGroup
	for i := 0; i < procs; i++ {
		wg.Add(1)
		go do_thread(niters/procs, &wg)
	}
	wg.Wait()

	if prof {
		pprof.StopCPUProfile()
	}
}