To: Alvaro Herrera <alvherre@commandprompt.com>
cc: Simon Riggs <simon@2ndquadrant.com>,
	List pgsql-patches <pgsql-patches@postgresql.org>
Subject: Re: [HACKERS] Hint Bits and Write I/O 
In-reply-to: <20080801231014.GM4321@alvh.no-ip.org> 
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	<20080801231014.GM4321@alvh.no-ip.org>
Comments: In-reply-to Alvaro Herrera <alvherre@commandprompt.com>
	message dated "Fri, 01 Aug 2008 19:10:14 -0400"
Date: Sat, 02 Aug 2008 00:24:46 -0400
Message-ID: <27349.1217651086@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

Alvaro Herrera <alvherre@commandprompt.com> writes:
> I think it makes sense to commit this patch now, per previous
> discussions on which we have agreed to make incremental changes.

Yeah, but at the same time there is merit in the argument that the
proposed patch hasn't actually been proven to be usable for anything.
I would be a lot happier if there were even a trivial proof-of-concept
plugin example submitted with it, just to prove that there were no
showstopper problems in the plugin design, like failure to pass
essential information or not getting the locking straight.

> I'm just wondering if the change of usage_count from 16 to 8 bits was
> discussed and agreed?

Umm ... it was not, but given that we have logic in there to limit the
usage_count to 5 or so, it's hard to argue that there's a big problem.

I confess to not having read the patch in detail --- where did the other
8 bits go to?

			regards, tom lane