Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 8037664FCC0 for ; Mon, 13 Oct 2008 07:17:46 -0300 (ADT) Received: from postgresql.org ([200.46.204.86]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 21285-04 for ; Mon, 13 Oct 2008 07:17:37 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from westnet.com (westnet.com [216.187.52.2]) by postgresql.org (Postfix) with ESMTP id 9F57264FCC6 for ; Mon, 13 Oct 2008 07:17:36 -0300 (ADT) Received: from westnet.com (localhost [127.0.0.1]) by westnet.com (8.14.0/8.14.0) with ESMTP id m9DAHV5j016773; Mon, 13 Oct 2008 06:17:31 -0400 (EDT) Received: from localhost (gsmith@localhost) by westnet.com (8.14.0/8.13.2/Submit) with ESMTP id m9DAHVI4016764; Mon, 13 Oct 2008 06:17:31 -0400 (EDT) X-Authentication-Warning: westnet.com: gsmith owned process doing -bs Date: Mon, 13 Oct 2008 06:17:31 -0400 (EDT) From: Greg Smith X-X-Sender: gsmith@westnet.com To: =?ISO-8859-1?Q?Mikkel_H=F8gh?= cc: pgsql-performance@postgresql.org Subject: Re: Drupal and PostgreSQL - performance issues? In-Reply-To: Message-ID: References: <2434A118-CEFA-43A9-BA88-006EC1F80326@hoegh.org> MIME-Version: 1.0 X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0 tagged_above=0 required=5 tests=none X-Spam-Level: Content-Type: TEXT/PLAIN; charset=X-UNKNOWN; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE X-Archive-Number: 200810/62 X-Sequence-Number: 31643 On Mon, 13 Oct 2008, Mikkel H=F8gh wrote: > Well, in that benchmark, what you say is only true for the Niagara=20 > processors. On the Opteron page, MySQL performance only drops slightly as= =20 > concurrency passes 50. That's partly because the upper limit on the graph only goes to 100=20 concurrent processes. Since the Opterons are faster, that's not a broad=20 enough scale to see how fast the right edge of the MySQL curve falls. You are right that the Niagara processors have a sharper decline than the= =20 more traditional platforms. The MySQL 5.0.20a graphs at=20 http://tweakers.net/reviews/657/6 has a nice comparison graph showing a=20 few different architectures that's also interesting. Anyway, you don't actually have to believe any of this; you've got a=20 testbed to try for yourself if you just crank the user count up. The main= =20 thing I was trying to suggest is that MySQL being a bit faster at 5 users= =20 is not unusual, but it's not really representative of which performs=20 better either. > In general, MySQL seems to have problems with some kinds of threading,=20 > since their perfomance on Mac OS X is crappy as well for that reason. One of the reasons (but by no means not the only one) that PostgreSQL uses= =20 a multi-process based architecture instead of a threaded one is because=20 thread library quality varies so much between platforms. -- * Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD=