X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id D7FE19DCBBD for ; Tue, 7 Mar 2006 15:22:27 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 10107-03 for ; Tue, 7 Mar 2006 15:22:27 -0400 (AST) 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 DD4D59DCA9B for ; Tue, 7 Mar 2006 15:22:24 -0400 (AST) Received: by noel.decibel.org (Postfix, from userid 1001) id 400785646A; Tue, 7 Mar 2006 13:22:22 -0600 (CST) Received: (hashcash-sendmail, from uid 1001); Tue, 7 Mar 2006 13:22:21 -0600 Date: Tue, 7 Mar 2006 13:22:21 -0600 From: "Jim C. Nasby" To: Mark Lewis Cc: Jeremy Haile , pgsql-performance@postgresql.org Subject: Re: Postgres and Ingres R3 / SAN Message-ID: <20060307192221.GA82989@pervasive.com> References: <20060306131355.A1227@ganymede.hub.org> <1141675112.28202.255960101@webmail.messagingengine.com> <20060307190019.GX82989@pervasive.com> <1141759250.4237.7.camel@archimedes> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1141759250.4237.7.camel@archimedes> 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: 1:20:060307:mark.lewis@mir3.com::dtOnAInZdvONlnox:000000000000000000 00000000000000000000000023Em X-Hashcash: 1:20:060307:jhaile@fastmail.fm::2e7v7JT2G5kjOmQm:0000000000000000000 0000000000000000000000000bxL X-Hashcash: 1:20:060307:pgsql-performance@postgresql.org::9RHXIg8yOenwown0:00000 0000000000000000000000003mkD X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0.109 required=5 tests=[AWL=0.109] X-Spam-Score: 0.109 X-Spam-Level: X-Archive-Number: 200603/74 X-Sequence-Number: 17511 On Tue, Mar 07, 2006 at 11:20:50AM -0800, Mark Lewis wrote: > On Tue, 2006-03-07 at 13:00 -0600, Jim C. Nasby wrote: > > ... > > > PostgreSQL on a SAN won't buy you what I think you think it will. It's > > essentially impossible to safely run two PostgreSQL installs off the > > same data files without destroying your data. What a SAN can buy you is > > disk-level replication, but I've no experience with that. > > It is possible to run two instances against the same SAN using tools > such as RedHat's Cluster Suite. We use that in-house as a cheap > alternative for Oracle clustering, although we're not using it for our > PostgreSQL servers yet. It's not for load balancing, just > active/passive fault tolerance. True, but the OP was talking about scaleability, which is not something you get with this setup. -- 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