Date: Fri, 20 Sep 2019 17:30:48 +0200
From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
To: Michael Paquier <michael@paquier.xyz>
Cc: Kuntal Ghosh <kuntalghosh.2007@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>,
	Robert Haas <robertmhaas@gmail.com>,
	Andres Freund <andres@anarazel.de>,
	Thomas Munro <thomas.munro@enterprisedb.com>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: subscriptionCheck failures on nightjar
Message-ID: <20190920153048.wpe27ht5lcs3zlrm@development>
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On Thu, Sep 19, 2019 at 01:23:05PM +0900, Michael Paquier wrote:
>On Wed, Sep 18, 2019 at 11:58:08PM +0200, Tomas Vondra wrote:
>> I kinda suspect it might be just a coincidence that it fails during that
>> particular test. What likely plays a role here is a checkpoint timing
>> (AFAICS that's the thing removing the file).  On most systems the tests
>> complete before any checkpoint is triggered, hence no issue.
>>
>> Maybe aggressively triggering checkpoints on the running cluter from
>> another session would do the trick ...
>
>Now that I recall, another thing I forgot to mention on this thread is
>that I patched guc.c to reduce the minimum of checkpoint_timeout to
>1s.

But even with that change you haven't managed to reproduce the issue,
right? Or am I misunderstanding?

regarss

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services