From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
cc: Michael Paquier <michael@paquier.xyz>, Andres Freund <andres@anarazel.de>,
        Thomas Munro <thomas.munro@enterprisedb.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: subscriptionCheck failures on nightjar
In-reply-to: <20190826132904.3ayuw36qzl2c4ktr@development>
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Comments: In-reply-to Tomas Vondra <tomas.vondra@2ndquadrant.com>
	message dated "Mon, 26 Aug 2019 15:29:04 +0200"
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Date: Mon, 26 Aug 2019 11:01:20 -0400
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Tomas Vondra <tomas.vondra@2ndquadrant.com> writes:
> I'm willing to take a stab at it, but to do that I need a way to
> reproduce it. Tom, you mentioned you've managed to reproduce it in a
> qemu instance, but that it took some fiddling with qemu parmeters or
> something. Can you share what exactly was necessary?

I don't recall exactly what I did anymore, and it was pretty fiddly
anyway.  Upthread I suggested

>> Now that we know where the problem is, you could probably make it highly
>> reproducible by inserting a sleep of a few msec between the rename and the
>> second fsync.

so why not try that first?

			regards, tom lane