X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (mx1.hub.org [200.46.208.251]) by postgresql.org (Postfix) with ESMTP id 1B70111F6083 for ; Tue, 25 Apr 2006 20:55:18 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.208.251]) (amavisd-new, port 10024) with ESMTP id 56088-05 for ; Tue, 25 Apr 2006 20:55:07 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey- Received: from noel.decibel.org (noel.decibel.org [67.100.216.10]) by postgresql.org (Postfix) with ESMTP id E467711F6081 for ; Tue, 25 Apr 2006 20:55:05 -0300 (ADT) Received: by noel.decibel.org (Postfix, from userid 1001) id AE86256427; Tue, 25 Apr 2006 18:55:05 -0500 (CDT) Received: (hashcash-sendmail, from uid 1001); Tue, 25 Apr 2006 18:55:04 -0500 Date: Tue, 25 Apr 2006 18:55:04 -0500 From: "Jim C. Nasby" To: Scott Marlowe Cc: Bill Moran , pgsql-performance@postgresql.org Subject: Re: Large (8M) cache vs. dual-core CPUs Message-ID: <20060425235504.GO97354@pervasive.com> References: <20060425141435.6c8c163c.wmoran@collaborativefusion.com> <1145990018.23538.234.camel@state.g2switchworks.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1145990018.23538.234.camel@state.g2switchworks.com> X-Operating-System: FreeBSD 6.0-RELEASE-p4 amd64 X-Distributed: Join the Effort! http://www.distributed.net User-Agent: Mutt/1.5.11 X-Hashcash: 1:20:060425:smarlowe@g2switchworks.com::lHKgrcDqKAtWgcHF:00000000000 0000000000000000000000007eGO X-Hashcash: 1:20:060425:wmoran@collaborativefusion.com::cVDout8rwVfl7mjK:0000000 00000000000000000000000006ok X-Hashcash: 1:20:060425:pgsql-performance@postgresql.org::kjAQMwZLckbJa44j:00000 0000000000000000000000002Mr6 X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200604/583 X-Sequence-Number: 18667 On Tue, Apr 25, 2006 at 01:33:38PM -0500, Scott Marlowe wrote: > On Tue, 2006-04-25 at 13:14, Bill Moran wrote: > > I've been given the task of making some hardware recommendations for > > the next round of server purchases. The machines to be purchased > > will be running FreeBSD & PostgreSQL. > > > > Where I'm stuck is in deciding whether we want to go with dual-core > > pentiums with 2M cache, or with HT pentiums with 8M cache. > > Given a choice between those two processors, I'd choose the AMD 64 x 2 > CPU. It's a significantly better processor than either of the Intel > choices. And if you get the HT processor, you might as well turn of HT > on a PostgreSQL machine. I've yet to see it make postgresql run faster, > but I've certainly seen HT make it run slower. Actually, believe it or not, a coworker just saw HT double the performance of pgbench on his desktop machine. Granted, not really a representative test case, but it still blew my mind. This was with a database that fit in his 1G of memory, and running windows XP. Both cases were newly minted pgbench databases with a scale of 40. Testing was 40 connections and 100 transactions. With HT he saw 47.6 TPS, without it was 21.1. I actually had IT build put w2k3 server on a HT box specifically so I could do more testing. -- Jim C. Nasby, Sr. Engineering Consultant jnasby@pervasive.com Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461