On 6/10/2004, at 4:06 AM, Tim Peters wrote:

[Michael Dunstan]
I'm seeing test failures in transience when running the tests for
Zope-2_7-branch (python 2.3.3) with garbage collection threshold0 set
to 1.
Whenever I see a test module import fauxtime, I run screaming in
terror.  This seems to be like running the multiprocess ZEO tests
(from which I run screaming daily <wink>):  "depending on" a gazillion
timing accidents you can't control, sometimes they just fail.

I ran the tests above in a loop a few hundred times on my box just
now, with no failures, Python 2.3.4 and command line:

test.py -vvLd -g1 --dir lib/python/Products/Transience/tests . testPathological

There's a big difference between my runs and yours, though:  running
the two tests took about 4.6 seconds on your box, but takes about 1.8
seconds on mine.  Now, for example, if I add

        oldtime.sleep(3)  # approximately 4.6 - 1.8, on the high side

right before

        map(self.t.__delitem__, r)

in testPathologicalRightBranching, then testPathologicalRightBranching
fails every time in a way similar to your reported failure -- and even
without -g1 on the command line.

If I change the sleep to 1.5, then (with -g1 again) sometimes it
passes, sometimes not, depending on how busy the box is doing other
stuff at the same time.

So that's A Problem.  Any test that adds a bunch of stuff to a
TransientObjectContainer and expects to *find* it all there later is
implicitly assuming that the test runs fast enough so that containees
don't vanish before their containedness is checked.  I suspect you're
seeing problems with -g1 here just because -g1 grossly slows the

Doh! For some reason I had written that explanation off before posting. The pattern of missing keys did not seem consistent enough at the time.

But, as you say, as soon as I comment out the use of faxtime and run those same two tests they both pass just fine.


Zope-Dev maillist - [EMAIL PROTECTED]
** No cross posts or HTML encoding! **
(Related lists - http://mail.zope.org/mailman/listinfo/zope-announce
http://mail.zope.org/mailman/listinfo/zope )

Reply via email to