Received: from localhost (maia-1.hub.org [200.46.204.191]) by postgresql.org (Postfix) with ESMTP id 38A569F9C35 for ; Tue, 12 Dec 2006 08:33:38 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.191]) (amavisd-new, port 10024) with ESMTP id 41702-05 for ; Tue, 12 Dec 2006 08:33:28 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from vms040pub.verizon.net (vms040pub.verizon.net [206.46.252.40]) by postgresql.org (Postfix) with ESMTP id 1D5419F9357 for ; Tue, 12 Dec 2006 08:33:29 -0400 (AST) Received: from osgiliath.mathom.us ([71.246.251.8]) by vms040.mailsrvcs.net (Sun Java System Messaging Server 6.2-6.01 (built Apr 3 2006)) with ESMTPA id <0JA500GZFUUX0FX2@vms040.mailsrvcs.net> for pgsql-performance@postgresql.org; Tue, 12 Dec 2006 06:32:57 -0600 (CST) Received: from localhost (localhost [127.0.0.1]) by osgiliath.mathom.us (Postfix) with ESMTP id 3A1D470AD1 for ; Tue, 12 Dec 2006 07:32:57 -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 DSiLyaTzcE+P for ; Tue, 12 Dec 2006 07:32:56 -0500 (EST) Received: by osgiliath.mathom.us (Postfix, from userid 1000) id 2ABFE70AD3; Tue, 12 Dec 2006 07:32:56 -0500 (EST) Date: Tue, 12 Dec 2006 07:32:55 -0500 From: Michael Stone Subject: Re: New to PostgreSQL, performance considerations In-reply-to: <2FC0D8E7-F8ED-452F-BB13-FB665B516E7F@purefiction.net> To: pgsql-performance@postgresql.org Mail-followup-to: pgsql-performance@postgresql.org Message-id: <20061212123252.GR16692@mathom.us> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii; format=flowed Content-disposition: inline X-Virus-Scanned: Debian amavisd-new at mathom.us X-Pgp-Fingerprint: 53 FF 38 00 E7 DD 0A 9C 84 52 84 C5 EE DF 7C 88 References: <8a0c7af10612110531sbb019ck259fb16d131fdb50@mail.gmail.com> <60psaq5t94.fsf@dba2.int.libertyrms.com> <20061211173105.GH16692@mathom.us> <20061211184726.GI16692@mathom.us> <457DA782.3060506@modgraph-usa.com> <8a0c7af10612111422x6bdcc0c2p7cbfeb5a7b0e0374@mail.gmail.com> <2FC0D8E7-F8ED-452F-BB13-FB665B516E7F@purefiction.net> User-Agent: Mutt/1.5.13 (2006-08-11) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200612/285 X-Sequence-Number: 22341 On Tue, Dec 12, 2006 at 12:29:29PM +0100, Alexander Staubo wrote: >I suspect the hardware's real maximum performance of the system is >~150 tps, but that the LSI's write cache is buffering the writes. I >would love to validate this hypothesis, but I'm not sure how. With fsync off? The write cache shouldn't really matter in that case. (And for this purpose that's probably a reasonable configuration.) Mike Stone