From: Tom Lane <tgl@sss.pgh.pa.us>
To: Michael Banck <mbanck@gmx.net>
cc: Andrew Dunstan <andrew@dunslane.net>, pgsql-hackers@lists.postgresql.org
Subject: Re: Maybe BF "timedout" failures are the client script's fault?
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Comments: In-reply-to Michael Banck <mbanck@gmx.net>
	message dated "Fri, 09 Jan 2026 22:32:55 +0100"
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Date: Fri, 09 Jan 2026 16:42:22 -0500
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Michael Banck <mbanck@gmx.net> writes:
> On Fri, Jan 09, 2026 at 03:41:03PM -0500, Tom Lane wrote:
>> Looking into the buildfarm client, I realized that it's assuming that
>> "sleep($wait_time)" is sufficient to wait for $wait_time seconds.
>> However, the Perl docs point out that sleep() can be interrupted by a
>> signal.  So now I'm suspicious that many of these failures are caused
>> by a stray signal waking up the wait_timeout thread prematurely.

> That might be the case for those other failures, but unfortunately, I
> think the fruitcrow failures are really because it gets stuck endlessly
> in the test_shm_mq test (it is always that one) and only the test
> timeout kicks it out.

If it's always the same test, then yeah that's evidence against
my theory (at least for fruitcrow's failures).

> I've ran that test manually quite a lot and either it finishes in 10-15
> seconds, or (presumably) never. This is not really easy to see in the
> public builfarm logs (at least I can't find it on a quick glance), but
> I've routinely checked the log timestamps of the runs, and they really
> take one hour (wait_timeout) in the case of a hang.

Hmm.  Then why is the BF report showing that the total runtime is
nowhere near that?  I wonder how those times are gathered ...

			regards, tom lane