[Python-Dev] Test failures in test_timeout (original) (raw)

Thomas Wouters thomas at xs4all.net
Thu Feb 16 18:43:26 CET 2006

I'm seeing spurious test failures in test_timeout, on my own workstation and on macteagle.python.org (now that it crashes less; Apple sent over some new memory.) The problem is pretty simple: both macteagle and my workstation live too closely, network-wise, to www.python.org:

class TimeoutTestCase(unittest.TestCase): [...] def setUp(self): [...] self.addr_remote = ('www.python.org', 80) [...] def testConnectTimeout(self): # Test connect() timeout _timeout = 0.001 self.sock.settimeout(_timeout)

    _t1 = time.time()
    self.failUnlessRaises(socket.error, self.sock.connect,
            self.addr_remote)

In other words, the test fails because www.python.org responds too quickly.

The test on my workstation only fails occasionally, but I do expect macteagle's failure to be more common (since it's connected to www.python.org through (literally) a pair of gigabit switches, whereas my workstation has to pass through a few more switches, two Junipers and some dark fiber.) Lowering the timeout has no effect, as far as I can tell, which is probably a granularity issue.

I'm thinking that it could probably try to connect to a less reliable website, but that's just moving the problem around (and possibly harassing an unsuspecting website, particularly around release-time.) Perhaps the test should try to connect to a known unconnecting site, like a firewalled port on www.python.org? Not something that refuses connections, just something that times out.

-- Thomas Wouters <thomas at xs4all.net>

Hi! I'm a .signature virus! copy me into your .signature file to help me spread!

More information about the Python-Dev mailing list