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 43DB49DC883 for ; Sun, 29 Jan 2006 11:43:25 -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 19584-09 for ; Sun, 29 Jan 2006 11:43:29 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey- Received: from vms046pub.verizon.net (vms046pub.verizon.net [206.46.252.46]) by postgresql.org (Postfix) with ESMTP id 9236F9DC80A for ; Sun, 29 Jan 2006 11:43:22 -0400 (AST) Received: from osgiliath.mathom.us ([70.108.47.21]) by vms046.mailsrvcs.net (Sun Java System Messaging Server 6.2-4.02 (built Sep 9 2005)) with ESMTPA id <0ITV00DS12CEXNWI@vms046.mailsrvcs.net> for pgsql-performance@postgresql.org; Sun, 29 Jan 2006 09:43:27 -0600 (CST) Received: from localhost (localhost [127.0.0.1]) by osgiliath.mathom.us (Postfix) with ESMTP id 1E5BC6E5D4 for ; Sun, 29 Jan 2006 10:43:26 -0500 (EST) Received: from osgiliath.mathom.us ([127.0.0.1]) by localhost (osgiliath.home.mathom.us [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 09900-02 for ; Sun, 29 Jan 2006 10:43:25 -0500 (EST) Received: by osgiliath.mathom.us (Postfix, from userid 1000) id 0ED986EA13; Sun, 29 Jan 2006 10:43:24 -0500 (EST) Date: Sun, 29 Jan 2006 10:43:24 -0500 From: Michael Stone Subject: Re: Huge Data sets, simple queries In-reply-to: <9e4684ce0601290325p4f284c57ndeaae13e6ce58fd7@mail.gmail.com> To: pgsql-performance@postgresql.org Mail-followup-to: pgsql-performance@postgresql.org Message-id: <20060129154323.GA9976@mathom.us> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii; format=flowed Content-disposition: inline X-Pgp-Fingerprint: 53 FF 38 00 E7 DD 0A 9C 84 52 84 C5 EE DF 7C 88 X-Virus-Scanned: Debian amavisd-new at mathom.us References: <007101c623a9$82207c10$0200a8c0@videobox> <9e4684ce0601290325p4f284c57ndeaae13e6ce58fd7@mail.gmail.com> User-Agent: Mutt/1.5.11 X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0.108 required=5 tests=[AWL=0.108] X-Spam-Score: 0.108 X-Spam-Level: X-Archive-Number: 200601/465 X-Sequence-Number: 16943 On Sun, Jan 29, 2006 at 12:25:23PM +0100, hubert depesz lubaczewski wrote: >hmm .. do i understand correctly that you're suggesting that using >raid 10 and/or hardware raid adapter might hurt disc subsystem >performance? could you elaborate on the reasons, please? I think it's been fairly well beaten to death that the low-end hardware raid adapters have lousy performance. It's not until you get into the range of battery-backed disk caches with 512M+ and multiple I/O channels that hardware raid becomes competitive with software raid. Mike Stone