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From: John Naylor <john.naylor@enterprisedb.com>
Date: Thu, 3 Feb 2022 13:34:28 -0500
Message-ID: <CAFBsxsGaZZTfLgd+H+VG6mxv5KfDxYf43tqOr_JqdwstCy=pLA@mail.gmail.com>
Subject: Re: do only critical work during single-user vacuum?
To: Robert Haas <robertmhaas@gmail.com>
Cc: Andres Freund <andres@anarazel.de>, Peter Geoghegan <pg@bowt.ie>, 
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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On Thu, Feb 3, 2022 at 1:06 PM Robert Haas <robertmhaas@gmail.com> wrote:
>
> On Thu, Dec 9, 2021 at 8:56 PM Andres Freund <andres@anarazel.de> wrote:
> > I think we should move *away* from single user mode, rather than the
> > opposite. It's a substantial code burden and it's hard to use.
>
> Yes. This thread seems to be largely devoted to the topic of making
> single-user vacuum work better, but I don't see anyone asking the
> question "why do we have a message that tells people to vacuum in
> single user mode in the first place?". It's basically bad advice, with
> one small exception that I'll talk about in a minute.

The word "advice" sounds like people have a choice, rather than the
system not accepting commands anymore. It would be much less painful
if the system closed connections and forbade all but superusers to
connect, but that sounds like a lot of work. (happy to be proven
otherwise)

-- 
John Naylor
EDB: http://www.enterprisedb.com