X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id E3F015350D for ; Mon, 9 May 2005 14:23:47 -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 57106-03 for ; Mon, 9 May 2005 17:23:43 +0000 (GMT) Received: from floppy.pyrenet.fr (news.pyrenet.fr [194.116.145.2]) by svr1.postgresql.org (Postfix) with ESMTP id 9DC1A53363 for ; Mon, 9 May 2005 14:23:41 -0300 (ADT) Received: by floppy.pyrenet.fr (Postfix, from userid 106) id DB97830953; Mon, 9 May 2005 19:21:31 +0200 (MET DST) From: William Yu X-Newsgroups: pgsql.performance Subject: Re: Whence the Opterons? Date: Mon, 09 May 2005 10:23:34 -0700 Organization: Hub.Org Networking Services Lines: 56 Message-ID: References: <4BAFBB6B9CC46F41B2AD7D9F4BBAF785026FF7D6@vt-pe2550-001.vantage.vantage.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Complaints-To: usenet@news.hub.org User-Agent: Mozilla Thunderbird 1.0 (X11/20041206) X-Accept-Language: en-us, en In-Reply-To: <4BAFBB6B9CC46F41B2AD7D9F4BBAF785026FF7D6@vt-pe2550-001.vantage.vantage.com> To: pgsql-performance@postgresql.org X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0 tagged_above=0 required=5 tests= X-Spam-Level: X-Archive-Number: 200505/114 X-Sequence-Number: 12278 Unfortunately, Anandtech only used Postgres just a single time in his benchmarks. And what it did show back then was a huge performance advantage for the Opteron architecture over Xeon in this case. Where the fastest Opterons were just 15% faster in MySQL/MSSQL/DB2 than the fastest Xeons, it was 100%+ faster in Postgres. He probably got rid of Postgres from his benchmark suite since it favors Opteron too much. As a general hardware review site, makes senses that he needs to get more neutral apps in order to get free systems to review and (ahem) ad dollars. That being said, I wouldn't get a quad Opteron system anyways now that the dual core Opterons are available. A DP+DC system would be faster and cheaper than a pure quad system. Unless of course, I needed a QP+DC for 8-way SMP. Anjan Dave wrote: > Wasn't the context switching issue occurring in specific cases only? > > I haven't seen any benchmarks for a 50% performance difference. Neither > have I seen any benchmarks of pure disk IO performance of specific > models of Dell vs HP or Sun Opterons. > > Thanks, > Anjan > >>EMC you can file an RPQ via your sales contacts to get it approved, >>though not sure how lengthy/painful that process might be, or if it's >>gonna be worth it. >> >>Read the article devoted to the v40z on anandtech.com. >> >>I am also trying to get a quad-Opteron versus the latest quad-XEON > > from > >>Dell (6850), but it's hard to justify a difference between a 15K dell >>versus a 30k v40z for a 5-8% performance gain (read the XEON Vs. > > Opteron > >>Database comparo on anandtech.com)... >> >>Thanks, >>Anjan >> > > > 15k vs 30k is indeed a big difference. But also realize that Postgres > has a specific benefit to Opterons versus Xeons. The context switching > storm happens less on an Opteron for some reason. > > I would venture a much greater benefit than 5-8%, more like 10-50%.