Received: from localhost (unknown [200.46.204.183])
	by mail.postgresql.org (Postfix) with ESMTP id 530136501B3
	for <pgsql-docs-postgresql.org@mail.postgresql.org>;
	Tue, 16 Dec 2008 19:38:26 -0400 (AST)
Received: from mail.postgresql.org ([200.46.204.86])
	by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024)
	with ESMTP id 34056-01 for
	<pgsql-docs-postgresql.org@mail.postgresql.org>;
	Tue, 16 Dec 2008 19:38:24 -0400 (AST)
X-Greylist: from auto-whitelisted by SQLgrey-1.7.6
Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130])
	by mail.postgresql.org (Postfix) with ESMTP id C8F6C6501CD
	for <pgsql-docs@postgresql.org>; Tue, 16 Dec 2008 19:38:23 -0400 (AST)
Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1])
	by sss.pgh.pa.us (8.14.2/8.14.2) with ESMTP id mBGNcHc6017529;
	Tue, 16 Dec 2008 18:38:17 -0500 (EST)
To: Bruce Momjian <bruce@momjian.us>
cc: Alvaro Herrera <alvherre@commandprompt.com>, valiouk@yahoo.co.uk,
	pgsql-docs@postgresql.org, dx k9 <bitsandbytes88@hotmail.com>
Subject: Re: [ADMIN] shared_buffers and shmmax 
In-reply-to: <200812162206.mBGM6rV19025@momjian.us> 
References: <200812162206.mBGM6rV19025@momjian.us>
Comments: In-reply-to Bruce Momjian <bruce@momjian.us>
	message dated "Tue, 16 Dec 2008 17:06:53 -0500"
Date: Tue, 16 Dec 2008 18:38:17 -0500
Message-ID: <17528.1229470697@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
X-Virus-Scanned: Maia Mailguard 1.0.1
X-Spam-Status: No, hits=0 tagged_above=0 required=5 tests=none
X-Spam-Level: 
X-Archive-Number: 200812/18
X-Sequence-Number: 5025

Bruce Momjian <bruce@momjian.us> writes:
> OK, updated patch.  I added item descriptions and removed Alvaro's
> paragraph;  I worked with Alvaro on this patch.

This still seems pretty misleading, as for example
  
>        <tbody>
>         <row>
>          <entry><xref linkend="guc-max-connections"></>
> !        <entry>1800 + 270 * <xref
> !        linkend="guc-max-locks-per-transaction"> bytes per connection</entry>
>         </row>

sounds like it might mean bytes per *active* connection, when of course
the correct way to figure it is by multiplying by max_connections.
If you're going to give a formula, why not just give a formula, eg

	(1800 + 270 * max_locks_per_transaction) * (max_connections + autovacuum_max_workers)

			regards, tom lane