Message-ID: <1f685b3a-7ec2-825e-bb2b-d87d78ad5bd9@pgmasters.net>
Date: Tue, 1 Mar 2022 12:22:25 -0600
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Subject: Re: Postgres restart in the middle of exclusive backup and the
 presence of backup_label file
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To: Nathan Bossart <nathandbossart@gmail.com>,
 Chapman Flack <chap@anastigmatix.net>
Cc: pgsql-hackers@lists.postgresql.org
References: <CAHg+QDfiM+WU61tF6=nPZocMZvHDzCK47Kneyb0ZRULYzV5sKQ@mail.gmail.com>
 <20220221172306.GA3698472@nathanxps13>
 <164589413251.1035.2695761148079719188.pgcf@coridan.postgresql.org>
 <20220226220614.GA673898@nathanxps13> <20220301055100.GA1002387@nathanxps13>
 <e6657efe-f7b1-0894-9807-453c01bad81a@pgmasters.net>
 <621E4529.1090601@anastigmatix.net> <20220301173208.GB1031413@nathanxps13>
From: David Steele <david@pgmasters.net>
In-Reply-To: <20220301173208.GB1031413@nathanxps13>
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On 3/1/22 11:32, Nathan Bossart wrote:
> On Tue, Mar 01, 2022 at 11:09:13AM -0500, Chapman Flack wrote:
>> On 03/01/22 09:44, David Steele wrote:
>>> Personally, I am in favor of removing it. We change/rename
>>> functions/tables/views when we need to, and this happens in almost every
>>> release.
>>
>> For clarification, is that a suggestion to remove the 'exclusive' parameter
>> in some later release, after using this release to default it to false and
>> reject calls with true?
> 
> My suggestion was to remove it in v15.  My impression is that David and
> Stephen agree, but I could be misinterpreting their responses.

I agree and I'm pretty sure Stephen does as well.

>> That way, at least, there would be a period of time where procedures
>> that currently work (by passing exclusive => false) would continue to work,
>> and could be adapted as time permits by removing that argument, with no
>> behavioral change.
> 
> I'm not sure if there's any advantage to kicking the can down the road.  At
> some point, we'll need to break existing backup scripts.  Will we be more
> prepared to do that in v17 than we are now?  We could maintain two sets of
> functions for a few releases and make it really clear in the documentation
> that pg_start/stop_backup() are going to be removed soon (and always emit a
> WARNING when they are used).  Would that address your concerns?

I think people are going to complain no matter what. If scripts are 
being maintained changing the name is not a big deal (though moving from 
exclusive to non-exclusive may be). If they aren't being maintained then 
they'll just blow up a few versions down the road when we remove the 
compatibility functions.

Regards,
-David