X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id EDD8CDA231 for ; Wed, 5 Oct 2005 20:46:31 -0300 (ADT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 58874-10 for ; Wed, 5 Oct 2005 23:46:28 +0000 (GMT) Received: from mail.baymountain.com (mail.baymountain.com [8.7.96.19]) by svr1.postgresql.org (Postfix) with SMTP id 781D9D9EA5 for ; Wed, 5 Oct 2005 20:46:26 -0300 (ADT) Received: (qmail 21450 invoked by uid 504); 5 Oct 2005 23:46:29 -0000 Received: from emil@baymountain.com by mail.baymountain.com by uid 501 with qmail-scanner-1.16 (spamassassin: 2.53. Clear:SA:0(0.0/7.0):. Processed in 0.269184 secs); 05 Oct 2005 23:46:29 -0000 Received: from unknown (HELO briggspack.com) (emil@briggspack.com@24.211.148.77) by mail.baymountain.com with SMTP; 5 Oct 2005 23:46:28 -0000 From: Emil Briggs Reply-To: emil@baymountain.com Organization: Baymountain, Inc. To: pgsql-performance@postgresql.org Subject: Re: Indexes on ramdisk Date: Wed, 5 Oct 2005 19:46:24 -0400 User-Agent: KMail/1.7.1 References: <200510042109.01849.emil@baymountain.com> <200510042341.23264.emil@baymountain.com> <33c6269f0510050803w72097bb5v526a0126af876af4@mail.gmail.com> In-Reply-To: <33c6269f0510050803w72097bb5v526a0126af876af4@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200510051946.24326.emil@baymountain.com> X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.038 required=5 tests=[AWL=-0.013, FORGED_RCVD_HELO=0.05] X-Spam-Level: X-Archive-Number: 200510/116 X-Sequence-Number: 14884 > What kind of order of improvement do you need to see? > A lot since the load on the system is expected to increase by up to 100% over the next 6 months. > What period are these number for? Were they collected over 1 hour, 1 day, 1 > month? > I thought I mentioned that in the earlier post but it was from a 2 hour period. It's a busy system. > How much Cache do you have on the controller? > 64Mbytes but I don't think that's an issue. As I mentioned in the first post the table that is the bottleneck has indexes on 15 columns and is seeing a lot of inserts, deletes and updates. The indexes are spread out over the 5 mirrors but it's still a couple of writes per mirror for each operation. I'm going to order an SSD which should give us a lot more headroom than trying to rearrange the RAID setup.