From owner-freebsd-threads@FreeBSD.ORG Sat May 22 09:58:24 2004 Return-Path: Delivered-To: freebsd-threads@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 16C0A16A4D3 for ; Sat, 22 May 2004 09:58:24 -0700 (PDT) Received: from ojoink.com (center.ojoink.com [216.65.123.180]) by mx1.FreeBSD.org (Postfix) with ESMTP id C5E5A43D1F for ; Sat, 22 May 2004 09:58:23 -0700 (PDT) (envelope-from amd64list@jpgsworld.com) Received: (qmail 7375 invoked by uid 89); 22 May 2004 17:02:10 -0000 Received: from unknown (HELO MAINBX.jpgsworld.com) (amd64list@jpgsworld.com@24.10.96.33) by center.ojoink.com with SMTP; 22 May 2004 17:02:10 -0000 Message-Id: <5.2.0.9.2.20040522094946.01588470@mail.ojoink.com> X-Sender: amd64list@jpgsworld.com@mail.ojoink.com X-Mailer: QUALCOMM Windows Eudora Version 5.2.0.9 Date: Sat, 22 May 2004 09:57:50 -0700 To: freebsd-threads@freebsd.org From: JG In-Reply-To: <40AF83E5.3090303@he.iki.fi> References: <5.2.0.9.2.20040522052606.0156fd70@mail.ojoink.com> <5.2.0.9.2.20040521154458.01627688@127.0.0.1> <5.2.0.9.2.20040521154458.01627688@127.0.0.1> <5.2.0.9.2.20040522052606.0156fd70@mail.ojoink.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed Subject: Re: Why is MySQL nearly twice as fast on Linux? X-BeenThere: freebsd-threads@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Threading on FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 22 May 2004 16:58:24 -0000 >It would be interesting if mysql is cpu-bound or disk bound in your tests >and if disk-bound, the relevant lines from dmesg would be appreciated. >FreeBSD (if I remember correctly) does not do elevator on disks by default >while most if not all linuxen do. That makes quite a difference on >disk-bound loads. >There are other things, like flush policy which behave differently by >default, since linux mounts filesystems asynchronously by default. >So if you want a fair comparison, all relevant parameters should be set to >same, if they are not by default. > >Pete I don't think this explains why the threading is messed up. The best FreeBSD config I've got on my AMD64 64-bit hardware was running 32-bit i386 FreeBSD with MySQL compiled with Linuxthreads. And those results were poor compared to Linux tests - they were just much higher than any other FreeBSD config. I's been established on the other lists that threading is not being handled properly to begin with. That has been the longtime crux with MySQL on FreeBSD, and why "Linuxthreads" has been recommended for so long as well, no? Also, we see almost nearly the same results running on a single CPU as we do when we run SMP - I don't believe the HD is to blame here.