Date: Sat, 5 Apr 2025 12:13:39 -0700
From: Noah Misch <noah@leadboat.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Michael Paquier <michael@paquier.xyz>,
	Nathan Bossart <nathandbossart@gmail.com>,
	Andres Freund <andres@anarazel.de>,
	Robert Pang <robertpang@google.com>,
	Kyotaro Horiguchi <horikyota.ntt@gmail.com>, robertmhaas@gmail.com,
	pgsql-hackers@postgresql.org
Subject: Re: Back-patch of: avoid multiple hard links to same WAL file after
 a crash
Message-ID: <20250405191339.8d.nmisch@google.com>
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On Sat, Apr 05, 2025 at 11:07:13AM -0400, Tom Lane wrote:
> Michael Paquier <michael@paquier.xyz> writes:
> > On Wed, Apr 02, 2025 at 05:29:00PM -0700, Noah Misch wrote:
> >> Here it is.  Making it fail three times took looping 1383s, 5841s, and 2594s.
> >> Hence, it couldn't be expected to catch the regression before commit, but it
> >> would have made sufficient buildfarm and CI noise in the day after commit.
> 
> > Hmm.  Not much of a fan of the addition of a test that has less than
> > 1% of reproducibility for the problem, even if it's good to see that
> > this can be made portable to run down to v13.
> 
> Yeah, it's good to have a test but I doubt we should commit it.
> Too many buildfarm cycles will be expended for too little result.

Current extent of our archive recovery restartpoint test coverage:

$ grep -c 'restartpoint starting' $(grep -rl 'restored log file' **/log) | grep -v :0
src/bin/pg_combinebackup/tmp_check/log/002_compare_backups_pitr1.log:1
src/test/recovery/tmp_check/log/020_archive_status_standby2.log:1
src/test/recovery/tmp_check/log/002_archiving_standby.log:1
src/test/recovery/tmp_check/log/020_archive_status_standby.log:1
src/test/recovery/tmp_check/log/035_standby_logical_decoding_standby.log:2

Since the 2025-02 releases made non-toy-size archive recoveries fail easily,
that's not enough.  If the proposed 3-second test is the wrong thing, what
instead?