From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Etsuro Fujita <fujita.etsuro@lab.ntt.co.jp>,
        Pg Hackers <pgsql-hackers@postgresql.org>,
        Rushabh Lathia <rushabh.lathia@gmail.com>,
        Michael Paquier <michael.paquier@gmail.com>,
        Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>
Subject: Re: postgres_fdw: perform UPDATE/DELETE .. RETURNING on a join
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
	message dated "Fri, 09 Feb 2018 15:24:26 -0500"
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Date: Sat, 10 Feb 2018 16:24:31 -0500
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Robert Haas <robertmhaas@gmail.com> writes:
> On Fri, Feb 9, 2018 at 1:33 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Robert Haas <robertmhaas@gmail.com> writes:
>>> Me neither.  I just ran the postgres_fdw regression tests 713 times in
>>> a row without a failure.  Tom, since you seem to be able to reproduce
>>> the problem locally, could you have a look at this proposed fix?

>> I'm a bit busy, but AFAICS it's just a timing thing, so try inserting
>> a sleep.  The attached is enough to reproduce rhinoceros' results
>> for me.

> Not for me, but when I pushed the pg_sleep up to 180 seconds, then it fa=
iled.

> With the proposed patch, it passes repeatedly for me with no sleep,
> and also passes for me with the sleep.  So I guess I'll commit this
> and see what the buildfarm thinks.

FWIW, I ran a thousand cycles of postgres_fdw installcheck without seeing
further problems.  So this fixes it at least for my configuration.
However, jaguarundi still shows a problem:

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=3Djaguarundi&dt=3D=
2018-02-10%2008%3A41%3A32

(previous run similar, so it's semi-reproducible even after this patch).
jaguarundi uses -DCLOBBER_CACHE_ALWAYS, so you might try a few repetitions
with that.

			regards, tom lane