On Wed, Jun 18, 2008 at 12:35 PM, Amaury Forgeot d'Arc <[EMAIL PROTECTED]> wrote: > Hello, > > 2008/6/18 Trent Nelson <[EMAIL PROTECTED]>: >> I gave my Windows buildbots a little bit of TLC last night. This little >> chestnut in test_multiprocessing.py around line 1346 is causing my buildbots >> to wedge more often than not: >> >> def test_listener_client(self): >> for family in self.connection.families: >> l = self.connection.Listener(family=family) >> p = self.Process(target=self._test, args=(l.address,)) >> p.set_daemon(True) >> p.start() >> conn = l.accept() >> self.assertEqual(conn.recv(), 'hello') >> p.join() >> l.close() >> >> The wedging will be a result of that accept() call. Not knowing anything >> about the module or the test suite, I can only assume that there's a race >> condition introduced between when the subprocess attempts to connect to the >> listener, versus when the l.accept() call is actually entered. (On the >> basis that a race condition would explain why sometimes it wedges and >> sometimes it doesn't.) >> >> Just FYI, the error in the buildbot log >> (http://www.python.org/dev/buildbot/all/x86%20W2k8%20trunk/builds/810/step-test/0) >> when this occurs is as follows: >> >> test_multiprocessing >> >> command timed out: 1200 seconds without output >> SIGKILL failed to kill process >> using fake rc=-1 >> program finished with exit code -1 >> remoteFailed: [Failure instance: Traceback from remote host -- Traceback >> (most recent call last): >> Failure: buildbot.slave.commands.TimeoutError: SIGKILL failed to kill process >> ] >> >> (The fact it can't be killed cleanly is a bug in Twisted's >> signalProcess('KILL') method, which doesn't work against Python processes >> that have entered accept() calls on Windows (which present the 'wedged' >> behaviour and have to be forcibly killed with OpenProcess/TerminateProcess).) > > I just found the cause of the problem ten minutes ago: > It seems that when a socket listens on the address "127.0.0.1" or > "localhost", another process cannot connect to it using the machine's > name (even from the same machine). > The best seems to listen with the empty address "". > > Index: Lib/multiprocessing/connection.py > =================================================================== > --- Lib/multiprocessing/connection.py (revision 64374) > +++ Lib/multiprocessing/connection.py (working copy) > @@ -49,7 +49,7 @@ > Return an arbitrary free address for the given family > ''' > if family == 'AF_INET': > - return ('localhost', 0) > + return ('', 0) > elif family == 'AF_UNIX': > return tempfile.mktemp(prefix='listener-', dir=get_temp_dir()) > elif family == 'AF_PIPE': > > And the test started to pass for me. > Can you please check this in if it works; I don't have svn access for > the moment. > > -- > Amaury Forgeot d'Arc
I am testing the patch locally now. _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
