Received: from localhost (maia-4.hub.org [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 73AAC9FB47C for ; Fri, 13 Apr 2007 05:53:00 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 31626-06 for ; Fri, 13 Apr 2007 05:52:56 -0300 (ADT) X-Greylist: delayed 00:16:47.828537 by SQLgrey-1.7.4 Received: from svr4.postgresql.org (svr4.postgresql.org [66.98.251.159]) by postgresql.org (Postfix) with ESMTP id 4564C9FB581 for ; Fri, 13 Apr 2007 05:52:55 -0300 (ADT) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.3 Received: from mail1.catalyst.net.nz (godel.catalyst.net.nz [202.78.240.40]) by svr4.postgresql.org (Postfix) with ESMTP id 78A935AF89C for ; Fri, 13 Apr 2007 08:36:07 +0000 (GMT) Received: from leibniz.catalyst.net.nz ([202.78.240.7] helo=[172.17.217.22]) by mail1.catalyst.net.nz with esmtpsa (TLS-1.0:RSA_ARCFOUR_MD5:16) (Exim 4.50) id 1HcHG8-000480-Ff; Fri, 13 Apr 2007 20:35:56 +1200 Subject: Re: Question about memory allocations From: Andrew McMillan To: Steve Cc: pgsql-performance@postgresql.org In-Reply-To: References: <233A9987-ABA5-4491-A304-FDA1F8FCD962@gmail.com> <14019.1176155022@sss.pgh.pa.us> <22512E5C-A60F-43E7-A370-257F7AF956FD@gmail.com> <16374.1176171185@sss.pgh.pa.us> <25200.1176213242@sss.pgh.pa.us> <26925.1176221294@sss.pgh.pa.us> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-QK4G7vttIRrX0VRSRy1E" Organization: Catalyst .Net Ltd Date: Fri, 13 Apr 2007 20:35:55 +1200 Message-Id: <1176453355.609.4.camel@hippy.mcmillan.net.nz> Mime-Version: 1.0 X-Mailer: Evolution 2.8.3 X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0.001 tagged_above=0 required=5 tests=BAYES_50=0.001 X-Spam-Level: X-Archive-Number: 200704/291 X-Sequence-Number: 24168 --=-QK4G7vttIRrX0VRSRy1E Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Tue, 2007-04-10 at 15:28 -0400, Steve wrote: >=20 > I'm trying to tune the memory usage of a new machine that has a -lot- of=20 > memory in it (32 gigs). ... >=20 > shared_buffers =3D 16GB Really? Wow! Common wisdom in the past has been that values above a couple of hundred MB will degrade performance. Have you done any benchmarks on 8.2.x that show that you get an improvement from this, or did you just take the "too much of a good thing is wonderful" approach? Cheers, Andrew. ------------------------------------------------------------------------- Andrew @ Catalyst .Net .NZ Ltd, PO Box 11-053, Manners St, Wellington WEB: http://catalyst.net.nz/ PHYS: Level 2, 150-154 Willis St DDI: +64(4)803-2201 MOB: +64(272)DEBIAN OFFICE: +64(4)499-2267 You have an unusual equipment for success. Be sure to use it properly. ------------------------------------------------------------------------- --=-QK4G7vttIRrX0VRSRy1E Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQBGH0DrjJA0f48GgBIRAgvCAJ0a/8mAlNMqBINvAGidiFOjcX42RACfYbgS Pdxg8kS5+UEfAfPABln5urY= =4mru -----END PGP SIGNATURE----- --=-QK4G7vttIRrX0VRSRy1E--