X-Original-To: pgsql-general-postgresql.org@localhost.postgresql.org Received: from localhost (mx1.hub.org [200.46.208.251]) by postgresql.org (Postfix) with ESMTP id 6EBD19FA334; Thu, 11 May 2006 19:19:37 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.208.251]) (amavisd-new, port 10024) with ESMTP id 97850-03; Thu, 11 May 2006 19:19:31 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey- X-Greylist: from auto-whitelisted by SQLgrey- Received: from noel.decibel.org (noel.decibel.org [67.100.216.10]) by postgresql.org (Postfix) with ESMTP id 32E6D9FA294; Thu, 11 May 2006 19:19:30 -0300 (ADT) Received: by noel.decibel.org (Postfix, from userid 1001) id 7843456437; Thu, 11 May 2006 17:19:29 -0500 (CDT) Received: (hashcash-sendmail, from uid 1001); Thu, 11 May 2006 17:19:28 -0500 Date: Thu, 11 May 2006 17:19:28 -0500 From: "Jim C. Nasby" To: Bruce Momjian Cc: "Joshua D. Drake" , Vivek Khera , "Pgsql-Performance ((E-mail))" , PostgreSQL General Subject: Re: [PERFORM] Arguments Pro/Contra Software Raid Message-ID: <20060511221928.GV99570@pervasive.com> References: <4460DE97.9040001@commandprompt.com> <200605100059.k4A0xtK09977@candle.pha.pa.us> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200605100059.k4A0xtK09977@candle.pha.pa.us> X-Operating-System: FreeBSD 6.0-RELEASE-p4 amd64 X-Distributed: Join the Effort! http://www.distributed.net User-Agent: Mutt/1.5.11 X-Hashcash: 1:20:060511:pgman@candle.pha.pa.us::QIrXfUbGQ2Jcnyn7:000000000000000 0000000000000000000000000Txd X-Hashcash: 1:20:060511:jd@commandprompt.com::Yh5wmUIydihw7RXB:00000000000000000 00000000000000000000000001JH X-Hashcash: 1:20:060511:vivek@khera.org::Jk2qrSEVCNXbw5rY:000KBq X-Hashcash: 1:20:060511:pgsql-performance@postgresql.org::NVVYPtxtQbMOtXQP:00000 0000000000000000000000006oi3 X-Hashcash: 1:20:060511:pgsql-general@postgresql.org::RBVZdavQM8U3ymdS:000000000 0000000000000000000000001g+x X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200605/508 X-Sequence-Number: 95300 On Tue, May 09, 2006 at 08:59:55PM -0400, Bruce Momjian wrote: > Joshua D. Drake wrote: > > Vivek Khera wrote: > > > > > > On May 9, 2006, at 11:51 AM, Joshua D. Drake wrote: > > > > > >> Sorry that is an extremely misleading statement. SATA RAID is > > >> perfectly acceptable if you have a hardware raid controller with a > > >> battery backup controller. > > >> > > >> And dollar for dollar, SCSI will NOT be faster nor have the hard drive > > >> capacity that you will get with SATA. > > > > > > Does this hold true still under heavy concurrent-write loads? I'm > > > preparing yet another big DB server and if SATA is a better option, I'm > > > all (elephant) ears. > > > > I didn't say better :). If you can afford, SCSI is the way to go. > > However SATA with a good controller (I am fond of the LSI 150 series) > > can provide some great performance. > > Basically, you can get away with cheaper hardware, but it usually > doesn't have the reliability/performance of more expensive options. > > You want an in-depth comparison of how a server disk drive is internally > better than a desktop drive: > > http://www.seagate.com/content/docs/pdf/whitepaper/D2c_More_than_Interface_ATA_vs_SCSI_042003.pdf BTW, someone (Western Digital?) is now offering SATA drives that carry the same MTBF/warranty/what-not as their SCSI drives. I can't remember if they actually claim that it's the same mechanisms just with a different controller on the drive... -- Jim C. Nasby, Sr. Engineering Consultant jnasby@pervasive.com Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461