To: Gregory Stark <stark@enterprisedb.com>
cc: "Alvaro Herrera" <alvherre@commandprompt.com>,
	"Josh Berkus" <josh@agliodbs.com>,
	"Heikki Linnakangas" <heikki@enterprisedb.com>,
	pgsql-hackers@postgresql.org,
	"Robert Treat" <xzilla@users.sourceforge.net>,
	"Peter Eisentraut" <peter_e@gmx.net>, "Greg Smith" <gsmith@gregsmith.com>,
	"Andreas Pflug" <pgadmin@pse-consulting.de>,
	"Decibel!" <decibel@decibel.org>
Subject: Re: Overhauling GUCS 
In-reply-to: <87od674hy6.fsf@oxford.xeocode.com> 
References: <48409D1E.3070208@agliodbs.com>
	<200806061624.29105.xzilla@users.sourceforge.net>
	<200806100937.38124.josh@agliodbs.com>
	<200806100949.17918.josh@agliodbs.com>
	<21875.1213122184@sss.pgh.pa.us>
	<484F7613.5070202@enterprisedb.com> <484FFF06.9010307@agliodbs.com>
	<20080611163847.GN5352@alvh.no-ip.org>
	<11913.1213218315@sss.pgh.pa.us>
	<87od674hy6.fsf@oxford.xeocode.com>
Comments: In-reply-to Gregory Stark <stark@enterprisedb.com>
	message dated "Thu, 12 Jun 2008 01:26:09 +0100"
Date: Wed, 11 Jun 2008 21:02:20 -0400
Message-ID: <25597.1213232540@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

Gregory Stark <stark@enterprisedb.com> writes:
> "Tom Lane" <tgl@sss.pgh.pa.us> writes:
>> I agree with that for pg_clog and friends, but I'm much more leery of
>> folding WAL into the same framework.

> Well it may still be worthwhile stealing buffers from shared_buffers even if
> we set a special flag marking them as owned by WAL and out of bounds for
> the normal buffer manager.

> At least that way we could always steal more if we want or return some, as
> long as we're careful about when we do it.

... and as long as you can acquire the WAL per-buffer management space out
of nowhere ...

			regards, tom lane