From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Justin Pryzby <pryzby@telsasoft.com>, Robert Haas <robertmhaas@gmail.com>,
        Andrew Dunstan <andrew@dunslane.net>, pgsql-hackers@postgresql.org,
        Thomas Munro <thomas.munro@gmail.com>,
        Melanie Plageman <melanieplageman@gmail.com>,
        Peter Eisentraut <peter.eisentraut@enterprisedb.com>,
        Daniel Gustafsson <daniel@yesql.se>
Subject: Re: Adding CI to our tree
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Tue, 18 Jan 2022 20:16:46 -0800"
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Date: Tue, 18 Jan 2022 23:39:20 -0500
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Andres Freund <andres@anarazel.de> writes:
> On 2022-01-18 21:50:07 -0500, Tom Lane wrote:
>> There is no reason for this script to be overriding Cluster.pm's
>> fsync = off setting.
>> This appears to go back to 917dc7d23 of 2016, so I think it just
>> predates our recognition that we should disable fsync in routine
>> tests.

> Yea, I noticed this too. I was wondering if there's a conceivable reason to
> actually want fsyncs, but I couldn't come up with one.

On the one hand, it feels a little wrong if our test suites never
reach our fsync calls at all.  On the other hand, it's not clear
what is meaningful about testing fsync when your test scenario
doesn't include a plug pull.

I'd be okay with having some exercise of the fsync code paths in
a test that is (a) designated for the purpose and (b) arranged
to not take an excessive amount of time, even under heavy load.
008_fsm_truncation.pl is neither of those things.  It seems
entirely random that it has fsync = on when we don't test that
elsewhere.

			regards, tom lane