Subject: Re: Postgres restart in the middle of exclusive backup and the
 presence of backup_label file
To: Nathan Bossart <nathandbossart@gmail.com>,
 Stephen Frost <sfrost@snowman.net>
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Cc: David Steele <david@pgmasters.net>, pgsql-hackers@lists.postgresql.org
From: Chapman Flack <chap@anastigmatix.net>
Message-ID: <621FC447.90502@anastigmatix.net>
Date: Wed, 2 Mar 2022 14:23:51 -0500
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On 03/01/22 20:03, Nathan Bossart wrote:
> Here is a new version of the patch with the following changes:

I did not notice this earlier (sorry), but there seems to remain in
backup.sgml a programlisting example that shows a psql invocation
for pg_backup_start, then a tar command, then another psql invocation
for pg_backup_stop.

I think that was only workable for the exclusive mode, and now it is
necessary to issue pg_backup_start and pg_backup_stop in the same session.

(The 'touch backup_in_progress' business seems a bit bogus now too,
suggesting an exclusivity remembered from bygone days.)

I am not sure what a workable, simple example ought to look like.
Maybe a single psql script issuing the pg_backup_start and the
pg_backup_stop, with a tar command in between with \! ?

Several bricks shy of production-ready, but it would give the idea.

Regards,
-Chap