Re: random isolation test failures

Excerpts from Noah Misch's message of lun sep 26 21:57:40 -0300 2011:

> These sporadic failures happen whenever the test case takes longer than
> deadlock_timeout (currently 100ms for these tests) to setup the deadlock.  I
> outlined some mitigating strategies here:
> http://archives.postgresql.org/message-id/20110727171438.GE18910@tornado.leadboat.com
>
> I'd vote for #1: let's double the deadlock_timeout until the failures stop.
> Other opinions?

I just tweaked isolationtester so that it collects the error messages
and displays them all together at the end of the test.  After seeing it
run, I didn't like it -- I think I prefer something more local, so that
in the only case where we call try_complete_step twice in the loop, we
report any errors in either.  AFAICS this would make both expected cases
behave identically in test output.  The only thing left to figure out is
where to store the error message between calls ... clearly Step is not
the right place for it.  I'm on it now, anyway.

--
Álvaro Herrera <alvherre@commandprompt.com>
The PostgreSQL Company - Command Prompt, Inc.
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