Message 64600 - Python tracker

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In-reply-to
Author	pitrou
Recipients	nnorwitz, pitrou
Date	2008年03月27日.16:22:38
SpamBayes Score	0.081930004
Marked as misclassified	No
Message-id	<1206634960.5.0.607743048032.issue2496@psf.upfronthosting.co.za>

Content
Hmm, I think I know what happens. t_bootstrap() in threadmodule.c calls the self.__bootstrap() method in the Thread object, and it is this method which sets the __stopped flag at its end, which in turns wakes up the join() method. The problem is that at this point, t_bootstrap() still (rightly) holds a reference to the Thread object, since it has a reference to its __bootstrap() method which is still running. Depending on how the operating system switches threads, this reference may or may not be released when the join() method returns. So I think it's the test that is flaky. Instead of calling the join() method, it should wait for the OS-level thread to finish. Or it should find another way of testing for the reference cycle.

Content

Hmm, I think I know what happens. t_bootstrap() in threadmodule.c calls
the self.__bootstrap() method in the Thread object, and it is this
method which sets the __stopped flag at its end, which in turns wakes up
the join() method.
The problem is that at this point, t_bootstrap() still (rightly) holds a
reference to the Thread object, since it has a reference to its
__bootstrap() method which is still running. Depending on how the
operating system switches threads, this reference may or may not be
released when the join() method returns.
So I think it's the test that is flaky. Instead of calling the join()
method, it should wait for the OS-level thread to finish. Or it should
find another way of testing for the reference cycle.

History
Date	User	Action	Args
2008年03月27日 16:22:40	pitrou	set	spambayes_score: 0.08193 -> 0.081930004 recipients: + pitrou, nnorwitz
2008年03月27日 16:22:40	pitrou	set	spambayes_score: 0.08193 -> 0.08193 messageid: <1206634960.5.0.607743048032.issue2496@psf.upfronthosting.co.za>
2008年03月27日 16:22:39	pitrou	link	issue2496 messages
2008年03月27日 16:22:38	pitrou	create

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