Got it. Thank you.
在 2017年4月22日星期六 UTC+8上午9:52:45，Matt Harden写道：
>
> There is no guarantee that any of your goroutines will execute even
> Lock(), much less Wait(), before the main goroutine executes Broadcast().
>
> On Thu, Apr 20, 2017 at 8:39 PM Allan <alla...@gmail.com <javascript:>>
> wrote:
>
>> I run a demo program to learn sync.NewCond：
>>
>> package main
>>
>> import (
>> "fmt"
>> "sync"
>> "time"
>> )
>>
>> var locker = new(sync.Mutex)
>> var cond = sync.NewCond(locker)
>>
>> func test(x int) {
>>
>> cond.L.Lock()
>> cond.Wait()
>> fmt.Println(x)
>> time.Sleep(time.Second * 1)
>> cond.L.Unlock()
>> }
>> func main() {
>> for i := 0; i < 10; i++ {
>> go test(i)
>> }
>> fmt.Println("start all")
>> cond.Broadcast()
>> time.Sleep(time.Second * 60)
>> }
>>
>>
>> When I run this program on Mac(Sierra 10.12.4)，it will print 0~9
>> randomly. But When I run it on Ubuntu 16.04, its result is not unique,
>> sometime just print "start all", sometimes print some numbers but not all.
>> I debug it with dlv, and the stack is as below:
>>
>> (dlv) bt
>> 0 0x0000000000453693 in runtime.futex
>> at /usr/local/go/src/runtime/sys_linux_amd64.s:388
>> 1 0x00000000004238de in runtime.futexsleep
>> at /usr/local/go/src/runtime/os_linux.go:62
>> 2 0x000000000040c370 in runtime.notetsleep_internal
>> at /usr/local/go/src/runtime/lock_futex.go:174
>> 3 0x000000000040c4e2 in runtime.notetsleepg
>> at /usr/local/go/src/runtime/lock_futex.go:206
>> 4 0x000000000043fff8 in runtime.timerproc
>> at /usr/local/go/src/runtime/time.go:209
>> 5 0x00000000004525f0 in runtime.goexit
>> at /usr/local/go/src/runtime/asm_amd64.s:2086
>> (dlv) goroutine
>> Thread 9327 at /usr/local/go/src/runtime/sys_linux_amd64.s:388
>> Goroutine 15:
>> Runtime: /usr/local/go/src/runtime/lock_futex.go:206 runtime.notetsleepg
>> (0x40c4e2)
>> User: /usr/local/go/src/runtime/lock_futex.go:206 runtime.notetsleepg
>> (0x40c4e2)
>> Go: /usr/local/go/src/runtime/time.go:97 runtime.addtimerLocked (0x43fc2e)
>> (dlv) goroutines
>> [15 goroutines]
>> Goroutine 1 - User: /usr/local/go/src/runtime/time.go:59 time.Sleep
>> (0x43fa55)
>> Goroutine 2 - User: /usr/local/go/src/runtime/proc.go:260
>> runtime.gopark (0x4283fa)
>> Goroutine 3 - User: /usr/local/go/src/runtime/proc.go:260
>> runtime.gopark (0x4283fa)
>> Goroutine 4 - User: /usr/local/go/src/runtime/proc.go:260
>> runtime.gopark (0x4283fa)
>> Goroutine 5 - User: /usr/local/go/src/runtime/sema.go:267
>> sync.runtime_notifyListWait (0x436341)
>> Goroutine 6 - User: /usr/local/go/src/runtime/sema.go:267
>> sync.runtime_notifyListWait (0x436341)
>> Goroutine 7 - User: /usr/local/go/src/runtime/sema.go:267
>> sync.runtime_notifyListWait (0x436341)
>> Goroutine 8 - User: /usr/local/go/src/runtime/sema.go:267
>> sync.runtime_notifyListWait (0x436341)
>> Goroutine 9 - User: /usr/local/go/src/runtime/sema.go:267
>> sync.runtime_notifyListWait (0x436341)
>> Goroutine 10 - User: /usr/local/go/src/runtime/sema.go:267
>> sync.runtime_notifyListWait (0x436341)
>> Goroutine 11 - User: /usr/local/go/src/runtime/sema.go:267
>> sync.runtime_notifyListWait (0x436341)
>> Goroutine 12 - User: /usr/local/go/src/runtime/sema.go:267
>> sync.runtime_notifyListWait (0x436341)
>> Goroutine 13 - User: /usr/local/go/src/runtime/sema.go:267
>> sync.runtime_notifyListWait (0x436341)
>> Goroutine 14 - User: /usr/local/go/src/runtime/sema.go:267
>> sync.runtime_notifyListWait (0x436341)
>> * Goroutine 15 - User: /usr/local/go/src/runtime/lock_futex.go:206
>> runtime.notetsleepg (0x40c4e2)
>>
>>
>> I'm not familiar to the raw code，can someone give me some help. Thx.
>>
>> BTW: My golang version is go version go1.7.4 linux/amd64.
>>
>> --
>> You received this message because you are subscribed to the Google Groups
>> "golang-nuts" group.
>> To unsubscribe from this group and stop receiving emails from it, send an
>> email to golang-nuts...@googlegroups.com <javascript:>.
>> For more options, visit https://groups.google.com/d/optout.
>>
>
--
You received this message because you are subscribed to the Google Groups
"golang-nuts" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to golang-nuts+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
