Received: from localhost (unknown [200.46.204.183]) by developer.postgresql.org (Postfix) with ESMTP id 4DF4C2E003A for ; Mon, 12 May 2008 23:11:03 -0300 (ADT) Received: from developer.postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 01045-07 for ; Mon, 12 May 2008 23:10:54 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from lists.commandprompt.com (host-159.commandprompt.net [207.173.203.159]) by developer.postgresql.org (Postfix) with ESMTP id C64B62E0039 for ; Mon, 12 May 2008 23:10:59 -0300 (ADT) Received: from jd-laptop (cmdalert.com [69.55.229.115]) (authenticated bits=0) by lists.commandprompt.com (8.13.8/8.13.8) with ESMTP id m4D2Bu4r025186 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Mon, 12 May 2008 19:11:57 -0700 Date: Mon, 12 May 2008 19:11:18 -0700 From: "Joshua D. Drake" To: Francisco Reyes Cc: Pgsql performance Subject: Re: RAID controllers for Postgresql on large setups Message-ID: <20080512191118.1b40324b@jd-laptop> In-Reply-To: References: Organization: Joshua D. Drake X-Mailer: Claws Mail 3.4.0 (GTK+ 2.12.9; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/2OG5vnglCJIx.WR3BoVUs=9"; protocol="application/pgp-signature"; micalg=PGP-SHA1 X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.0 (lists.commandprompt.com [207.173.203.159]); Mon, 12 May 2008 19:11:58 -0700 (PDT) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200805/149 X-Sequence-Number: 30117 --Sig_/2OG5vnglCJIx.WR3BoVUs=9 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Mon, 12 May 2008 22:04:03 -0400 Francisco Reyes wrote: > Inheritted a number of servers and I am starting to look into the > hardware. >=20 > So far what I know from a few of the servers > Redhat servers. > 15K rpm disks, 12GB to 32GB of RAM. > Adaptec 2120 SCSI controller (64MB of cache). >=20 > The servers have mostly have 12 drives in RAID 10. > We are going to redo one machine to compare RAID 10 vs RAID 50.=20 > Mostly to see if the perfomance is close, the space gain may be > usefull. Most likely you have a scsi onboard as well I am guessing. You shouldn't bother with the 2120. My tests show it is a horrible controller for random writes. Comparing software raid on an LSI onboard for an IBM 345 versus a 2120s using hardware raid 10, the software raid completely blew the adaptec away. Joshua D. Drake --=20 The PostgreSQL Company since 1997: http://www.commandprompt.com/=20 PostgreSQL Community Conference: http://www.postgresqlconference.org/ United States PostgreSQL Association: http://www.postgresql.us/ Donate to the PostgreSQL Project: http://www.postgresql.org/about/donate --Sig_/2OG5vnglCJIx.WR3BoVUs=9 Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQFIKPjGATb/zqfZUUQRAs2wAKCiMSwYFF2dYYw4+v7FtqskIYBtswCdGdFd UD1yjsleqkk446IiYaol4+g= =+MUg -----END PGP SIGNATURE----- --Sig_/2OG5vnglCJIx.WR3BoVUs=9--