From: Tom Lane <tgl@sss.pgh.pa.us>
To: Stephen Frost <sfrost@snowman.net>
cc: Peter Eisentraut <peter.eisentraut@enterprisedb.com>,
        Alvaro Herrera <alvherre@alvh.no-ip.org>,
        Laurenz Albe <laurenz.albe@cybertec.at>,
        "Bossart,
    Nathan" <bossartn@amazon.com>,
        Michael Paquier <michael@paquier.xyz>,
        Bernd Helmle <mailings@oopsware.de>,
        "tsunakawa.takay@fujitsu.com" <tsunakawa.takay@fujitsu.com>,
        "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: Change default of checkpoint_completion_target
In-reply-to: <20210119194748.GP27507@tamriel.snowman.net>
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Comments: In-reply-to Stephen Frost <sfrost@snowman.net>
	message dated "Tue, 19 Jan 2021 14:47:48 -0500"
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Date: Tue, 19 Jan 2021 15:12:34 -0500
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Stephen Frost <sfrost@snowman.net> writes:
> In passing, I noticed that we have a lot of documentation like:

> This parameter can only be set in the postgresql.conf file or on the
> server command line.

> ... which hasn't been true since the introduction of ALTER SYSTEM.

Well, it's still true if you understand "the postgresql.conf file"
to cover whatever's included by postgresql.conf, notably
postgresql.auto.conf (and the include facility existed long before
that, too, so you needed the expanded interpretation even then).
Still, I take your point that it's confusing.

I like your suggestion of shortening all of these to be "can only be set
at server start", or maybe better "cannot be changed after server start".
I'm not sure whether or not we really need new text elsewhere; I think
section 20.1 is pretty long already.

			regards, tom lane