To: Greg Smith <gsmith@gregsmith.com>
cc: Peter Eisentraut <peter_e@gmx.net>, pgsql-hackers@postgresql.org,
	Josh Berkus <josh@agliodbs.com>
Subject: Re: Overhauling GUCS 
In-reply-to: <Pine.GSO.4.64.0806020452220.26912@westnet.com> 
References: <48409D1E.3070208@agliodbs.com>
	<200806010032.53337.peter_e@gmx.net>
	<Pine.GSO.4.64.0806020452220.26912@westnet.com>
Comments: In-reply-to Greg Smith <gsmith@gregsmith.com>
	message dated "Mon, 02 Jun 2008 06:24:26 -0400"
Date: Mon, 02 Jun 2008 10:12:06 -0400
Message-ID: <17932.1212415926@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

Greg Smith <gsmith@gregsmith.com> writes:
> Joshua has been banging a drum for a while now that all this data needs to 
> get pushing into the database itself.

This is, very simply, not going to happen.  Shall we go over the reasons
why not, one more time?

1. Quite a few of the GUC parameters are needed *before* one can ever
read the database; in particular the ones about file locations and
shared memory sizing.

2. Suppose you change a parameter in a way that breaks the DB (eg,
set shared_buffers to a value larger than your kernel allows) and
try to restart.  Database doesn't start.  If the parameter can only
be changed back within an operating database, you're hosed.

I have no objection to providing alternative ways to edit the
configuration data, but the primary source of the settings is
going to continue to be an editable text file.  Any proposals for
alternatives-to-a-text-editor have to work within that reality.

			regards, tom lane