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To: Alvaro Herrera <alvherre@commandprompt.com>
cc: Greg Stark <gsstark@mit.edu>, Pierre C <lists@peufeu.com>,
	Greg Smith <greg@2ndquadrant.com>, Dave Crooke <dcrooke@gmail.com>,
	Paul McGarry <paul@paulmcgarry.com>, pgsql-performance@postgresql.org
Subject: Re: shared_buffers advice 
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Comments: In-reply-to Alvaro Herrera <alvherre@commandprompt.com>
	message dated "Tue, 16 Mar 2010 19:20:58 -0300"
Date: Tue, 16 Mar 2010 18:25:26 -0400
Message-ID: <15895.1268778326@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Alvaro Herrera <alvherre@commandprompt.com> writes:
> Tom Lane escribió:
>> That's not going to do anything towards reducing the actual I/O volume.
>> Although I suppose it might be useful if it just cuts the number of
>> seeks.

> Oh, they had no problems with I/O volume.  It was relation extension
> lock that was heavily contended for them.

Really?  I guess that serialized all the I/O ... I'll bet if we got rid
of that locking somehow, they *would* have a problem with I/O volume.

			regards, tom lane