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In-Reply-To: <20220216181846.4syh3mnq5qzjrdiz@alap3.anarazel.de>
From: Peter Geoghegan <pg@bowt.ie>
Date: Wed, 16 Feb 2022 10:27:38 -0800
Message-ID: <CAH2-Wz=gkPvzf+H6nXtcxT2STGvh7-hmys4X-oGsihddZQte1Q@mail.gmail.com>
Subject: Re: do only critical work during single-user vacuum?
To: Andres Freund <andres@anarazel.de>
Cc: Robert Haas <robertmhaas@gmail.com>, Masahiko Sawada <sawada.mshk@gmail.com>, 
	John Naylor <john.naylor@enterprisedb.com>, 
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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On Wed, Feb 16, 2022 at 10:18 AM Andres Freund <andres@anarazel.de> wrote:
> > I'm pretty sure that some people believe that wraparound can cause
> > actual data corruption
>
> Well, historically they're not wrong.

True, but the most recent version where that's actually possible is
PostgreSQL 8.0, which was released in early 2005. That was a very
different time for the project. I don't think that people believe that
wraparound can cause data corruption because they remember a time when
it really could. It seems like general confusion to me (which could
have been avoided).

At a minimum, we ought to be very clear on the fact that Postgres
isn't going to just let your database become corrupt in some more or
less predictable way. The xidStopLimit thing is pretty bad, but it's
still much better than that.

-- 
Peter Geoghegan