Message-ID: <e61e8b08-e67e-4d45-9e66-1eaa82d49f16@pgmasters.net>
Date: Thu, 11 Apr 2024 09:36:11 +1000
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Subject: Re: post-freeze damage control
To: Michael Paquier <michael@paquier.xyz>
Cc: "Andrey M. Borodin" <x4mmm@yandex-team.ru>,
 Alvaro Herrera <alvherre@alvh.no-ip.org>,
 Stefan Fercot <stefan.fercot@protonmail.com>,
 Robert Haas <robertmhaas@gmail.com>,
 Tomas Vondra <tomas.vondra@enterprisedb.com>,
 "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
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 <ZhXUYBXTWvF4OaPm@paquier.xyz>
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From: David Steele <david@pgmasters.net>
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On 4/10/24 09:50, Michael Paquier wrote:
> On Wed, Apr 10, 2024 at 09:29:38AM +1000, David Steele wrote:
>> Even so, only keeping WAL for the last backup is a dangerous move in any
>> case. Lots of things can happen to a backup (other than bugs in the
>> software) so keeping WAL back to the last full (or for all backups) is
>> always an excellent idea.
> 
> Yeah, that's an excellent practive, but is why I'm less worried for
> this feature.  The docs at [1] caution about "not to remove earlier
> backups if they might be needed when restoring later incremental
> backups".  Like Alvaro said, should we insist a bit more about the WAL
> retention part in this section of the docs, down to the last full
> backup?

I think that would make sense in general. But if we are doing it because 
we lack confidence in the incremental backup feature maybe that's a sign 
that the feature should be released as experimental (or not released at 
all).

Regards,
-David