From: Tom Lane <tgl@sss.pgh.pa.us>
To: Amit Kapila <amit.kapila16@gmail.com>
cc: Mark Dilger <hornschnorter@gmail.com>,
        Andrew Dunstan <andrew.dunstan@2ndquadrant.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Windows buildfarm members vs. new async-notify isolation test
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Comments: In-reply-to Amit Kapila <amit.kapila16@gmail.com>
	message dated "Wed, 04 Dec 2019 10:31:18 +0530"
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Date: Wed, 04 Dec 2019 00:12:27 -0500
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Amit Kapila <amit.kapila16@gmail.com> writes:
> On Tue, Dec 3, 2019 at 10:10 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Hmm ... just looking at the code again, could it be that there's
>> no well-placed CHECK_FOR_INTERRUPTS?  Andrew, could you see if
>> injecting one in what 790026972 added to postgres.c helps?

> I also tried to analyze this failure and it seems this is a good bet,
> but I am also wondering why we have never seen such a timing issue in
> other somewhat similar tests.  For ex.,  one with comment (#
> Cross-backend notification delivery.).  Do they have a better way of
> ensuring that the notification will be received or is it purely
> coincidental that they haven't seen such a symptom?

TBH, my bet is that this *won't* fix it, but it seemed like an easy
thing to test.  For this to fix it, you'd have to suppose that we
never do a CHECK_FOR_INTERRUPTS during a COMMIT command, which is
improbable at best.

			regards, tom lane