Received: from maia.hub.org (unknown [200.46.204.183]) by mail.postgresql.org (Postfix) with ESMTP id 24E37632C98 for ; Fri, 19 Mar 2010 06:09:14 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 13143-02 for ; Fri, 19 Mar 2010 09:09:03 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from smtp1.hi-media-techno.com (smtp1.hi-media-techno.com [195.158.241.85]) by mail.postgresql.org (Postfix) with ESMTP id 988E9632A73 for ; Fri, 19 Mar 2010 06:09:03 -0300 (ADT) Received: from localhost (localhost [127.0.0.1]) by smtp1.hi-media-techno.com (Postfix) with ESMTP id 9D25493B92; Fri, 19 Mar 2010 10:09:01 +0100 (CET) Received: from smtp1.hi-media-techno.com ([127.0.0.1]) by localhost (smtp1.backbone.hi-media-techno.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 077WYD32IQG5; Fri, 19 Mar 2010 10:09:01 +0100 (CET) Received: from mail1.hi-media-techno.com (unknown [192.168.27.17]) by smtp1.hi-media-techno.com (Postfix) with ESMTP id 576E993B6C; Fri, 19 Mar 2010 10:09:01 +0100 (CET) Received: from localhost (localhost.localdomain [127.0.0.1]) by mail1.hi-media-techno.com (Postfix) with ESMTP id 3D6C94A618; Fri, 19 Mar 2010 10:09:01 +0100 (CET) X-Virus-Scanned: amavisd-new at mail1.hi-media-techno.com Received: from mail1.hi-media-techno.com ([127.0.0.1]) by localhost (mail1.hi-media-techno.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id delslKXXfg-t; Fri, 19 Mar 2010 10:09:00 +0100 (CET) Received: from dim (unknown [83.167.62.196]) by mail1.hi-media-techno.com (Postfix) with ESMTPSA id E917F9933D; Fri, 19 Mar 2010 10:09:00 +0100 (CET) Received: by dim (Postfix, from userid 1000) id E8F8113F5F; Fri, 19 Mar 2010 10:04:00 +0100 (CET) From: Dimitri Fontaine To: Corin Cc: pgsql-performance@postgresql.org Subject: Re: mysql to postgresql, performance questions Organization: Hi-Media References: <4BA23936.2030507@gmail.com> User-Mail-Address: dfontaine@hi-media.com Date: Fri, 19 Mar 2010 10:04:00 +0100 In-Reply-To: <4BA23936.2030507@gmail.com> (Corin's message of "Thu, 18 Mar 2010 15:31:18 +0100") Message-ID: <87ocikwum7.fsf@hi-media-techno.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.0.50 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-2.599 tagged_above=-10 required=5 tests=BAYES_00=-2.599 X-Spam-Level: X-Archive-Number: 201003/234 X-Sequence-Number: 38059 Corin writes: > I'm running quite a large social community website (250k users, 16gb > database). We are currently preparing a complete relaunch and thinking about > switching from mysql 5.1.37 innodb to postgresql 8.4.2. The database server > is a dual dualcore operton 2216 with 12gb ram running on debian amd64. > > For a first impression I ran a simple query on our users table (snapshot For more serious impression and realistic figures, you could use tsung atop the http side of your application and compare how it performs given a certain load of concurrent users. In your situation I'd expect to win a lot going to PostgreSQL on concurrency scaling. Tsung is made to test that. http://tsung.erlang-projects.org/ Regards, -- dim