From: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
Subject: Re: pgsql: Improve stability of TAP test for synchronous replication
To: Michael Paquier <michael@paquier.xyz>,
 pgsql-committers@lists.postgresql.org
References: <E1hq6VT-0002qO-AH@gemulon.postgresql.org>
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Message-ID: <16da29fa-d504-1380-7095-40de586dc038@2ndQuadrant.com>
Date: Wed, 24 Jul 2019 14:17:14 -0400
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On 7/23/19 9:55 PM, Michael Paquier wrote:
> Improve stability of TAP test for synchronous replication
>
> Slow buildfarm machines have run into issues with this TAP test caused
> by a race condition related to the startup of a set of standbys, where
> it is possible to finish with an unexpected order in the WAL sender
> array of the primary.
>
> This closes the race condition by making sure that any standby started
> is registered into the WAL sender array of the primary before starting
> the next one based on lookups of pg_stat_replication.
>
> Backpatch down to 9.6 where the test has been introduced.
>
> Author: Michael Paquier
> Reviewed-by: Álvaro Herrera, Noah Misch
> Discussion: https://postgr.es/m/20190617055145.GB18917@paquier.xyz
> Backpatch-through: 9.6
>
> Branch
> ------
> master
>
> Details
> -------
> https://git.postgresql.org/pg/commitdiff/7d81bdc8c0ce838efa248928065e9b2da829f981
>
> Modified Files
> --------------
> src/test/recovery/t/007_sync_rep.pl | 42 +++++++++++++++++++++++++++++--------
> 1 file changed, 33 insertions(+), 9 deletions(-)
>


This broke our perl coding rules:


./src/test/recovery/t/007_sync_rep.pl: Subroutine "start_standby_and_wait" does not end with "return" at line 33, column 1.  See page 197 of PBP.  (Severity: 5)

cheers

andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services