Re: Fixing WAL instability in various TAP tests

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Mark Dilger <mark.dilger@enterprisedb.com>
Cc: Michael Paquier <michael@paquier.xyz>, Andrew Dunstan <andrew@dunslane.net>, Noah Misch <noah@leadboat.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2021-09-28T19:00:13Z
Lists: pgsql-hackers

Attachments

Mark Dilger <mark.dilger@enterprisedb.com> writes:
> Perhaps having the bloom index messed up answers that, though.  I think it should be easy enough to get the path to the heap main table fork and the bloom main index fork for both the primary and standby and do a filesystem comparison as part of the wal test.  That would tell us if they differ, and also if the differences are limited to just one or the other.

I think that's probably overkill, and definitely out-of-scope for
contrib/bloom.  If we fear that WAL replay is not reproducing the data
accurately, we should be testing for that in some more centralized place.

Anyway, I confirmed my diagnosis by adding a delay in WAL apply
(0001 below); that makes this test fall over spectacularly.
And 0002 fixes it.  So I propose to push 0002 as soon as the
v14 release freeze ends.

Should we back-patch 0002?  I'm inclined to think so.  Should
we then also back-patch enablement of the bloom test?  Less
sure about that, but I'd lean to doing so.  A test that appears
to be there but isn't actually invoked is pretty misleading.

			regards, tom lane

Commits

  1. Fix instability in contrib/bloom TAP tests.

  2. Re-enable contrib/bloom's TAP tests.