From owner-freebsd-amd64@FreeBSD.ORG Fri Jul 29 09:32:31 2005 Return-Path: X-Original-To: freebsd-amd64@freebsd.org Delivered-To: freebsd-amd64@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 8955916A41F for ; Fri, 29 Jul 2005 09:32:31 +0000 (GMT) (envelope-from ray@redshift.com) Received: from outgoing.redshift.com (outgoing.redshift.com [207.177.231.8]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3460143D45 for ; Fri, 29 Jul 2005 09:32:31 +0000 (GMT) (envelope-from ray@redshift.com) Received: from workstation (216-228-19-21.dsl.redshift.com [216.228.19.21]) by outgoing.redshift.com (Postfix) with SMTP id 2CEC0979B6; Fri, 29 Jul 2005 02:32:30 -0700 (PDT) Message-Id: <3.0.1.32.20050729023234.00a8afb8@pop.redshift.com> X-Mailer: na X-Sender: redshift.com Date: Fri, 29 Jul 2005 02:32:34 -0700 To: Martin Cracauer From: ray@redshift.com Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: freebsd-amd64@freebsd.org Subject: Re: Benchmarks: AMD64 vs i386 on Dual 246 Opteron X-BeenThere: freebsd-amd64@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Porting FreeBSD to the AMD64 platform List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 29 Jul 2005 09:32:31 -0000 At 07:35 PM 7/28/2005 -0400, Martin Cracauer wrote: | > While this sounded like a long shot, I loaded FreeBSD 5.4 i386 on the machine | > and after applying the exact same configuration to the OS, Apache, PHP and | > MySQL, re-ran the benchmarks. Much to my surprise, just changing the OS from 64 | > bit to 32 bit caused the machine to double in speed. The results are attached | > in an Excel spreadsheet. So the exact same machine, running the identical | > configuration, performed roughly twice as fast when running FreeBSD 5.4 i386 vs | > FreeBSD 5.4 AMD64. Something about this seems so wrong to me :-) | | I'm sorry but I cannot support these findings. I don't have | cut'n'paste numbers handy, but generally 64 bits speed up things quite | a bit for me. I have seen slowdown in 64 bit mode in e.g. bzip2 but | generally there is a speedup. On the AMD64, I am pretty sure that I did *not* include the following lines like I normally do on the i386: options SMP # Symmetric MultiProcessor Kernel device apic # I/O APIC I seem to remember on one of the first AMD64 installs I did, the apic line produced some sort of compiler error. However, in looking over the AMD64 branch on another machine (with 5.3 on it), I do see there is a SMP config file that includes the GENERIC conf file and then tags on options SMP. So this may be a problem in my benchmarks and I will have to repeat the tests when I have another Dual Opteron server down here. For whatever reason, I was under the impression the AMD64 kernel config file supported SMP by default, but now I'm wondering. Ray