Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 745872E02D6 for ; Mon, 3 Mar 2008 21:11:47 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 05555-05-6 for ; Mon, 3 Mar 2008 21:11:44 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from westnet.com (westnet.com [216.187.52.2]) by postgresql.org (Postfix) with ESMTP id 31A772E02B9 for ; Mon, 3 Mar 2008 21:11:44 -0400 (AST) Received: from westnet.com (localhost [127.0.0.1]) by westnet.com (8.14.0/8.14.0) with ESMTP id m241BgRr024948; Mon, 3 Mar 2008 20:11:42 -0500 (EST) Received: from localhost (gsmith@localhost) by westnet.com (8.14.0/8.13.2/Submit) with ESMTP id m241BgfV024945; Mon, 3 Mar 2008 20:11:42 -0500 (EST) X-Authentication-Warning: westnet.com: gsmith owned process doing -bs Date: Mon, 3 Mar 2008 20:11:42 -0500 (EST) From: Greg Smith X-X-Sender: gsmith@westnet.com To: alan bryan cc: pgsql-performance@postgresql.org Subject: Re: Performance tuning on FreeBSD In-Reply-To: <892916310803031539scffd5bchcce5a848b3a57a32@mail.gmail.com> Message-ID: References: <892916310803031539scffd5bchcce5a848b3a57a32@mail.gmail.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200803/41 X-Sequence-Number: 28995 On Mon, 3 Mar 2008, alan bryan wrote: >> pgbench -c 100 -t 1000 testdb > tps = 558.013714 (excluding connections establishing) > > Just for testing, I tried turning off fsync and got: > tps = 4061.662041 (excluding connections establishing) This is odd. ~500 is what I expect from this test when there is no write cache to accelerate fsync, while ~4000 is normal for your class of hardware when you have such a cache. Since you say your 3Ware card is setup with a cache and a BBU, that's suspicious--you should be able to get around 4000 with fsync on. Any chance you have the card set to write-through instead of write-back? That's the only thing that comes to mind that would cause this. -- * Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD