From owner-freebsd-threads@FreeBSD.ORG Sun May 23 22:06:12 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 1B0F116A4CE; Sun, 23 May 2004 22:06:12 -0700 (PDT) Received: from mail.pcnet.com (mail.pcnet.com [204.213.232.4]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9100F43D4C; Sun, 23 May 2004 22:06:11 -0700 (PDT) (envelope-from eischen@vigrid.com) Received: from mail.pcnet.com (mail.pcnet.com [204.213.232.4]) by mail.pcnet.com (8.12.10/8.12.1) with ESMTP id i4O55T8Q022170; Mon, 24 May 2004 01:05:29 -0400 (EDT) Date: Mon, 24 May 2004 01:05:29 -0400 (EDT) From: Daniel Eischen X-Sender: eischen@pcnet5.pcnet.com To: mike In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: David Xu cc: freebsd-threads@freebsd.org 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: Mon, 24 May 2004 05:06:12 -0000 On Sun, 23 May 2004, mike wrote: > > > > > Note that default mysql table type is mysql, which uses Giant Lock when > > doing update on table, it does not support concurrent update, each thread > > wants to update the table will be serialized, fix me if I am wrong, but some > > years ago, mysql book tells me the fact, you might need to look other types, > > for example, BDB or innodb. 50% cpu usage on SMP machine is normal for > > MySQL server using mysql table type. > > > > David Xu > > i just want to note - either way, running the same benchmarking utilities > on linux shows linux outperforming freebsd hands down. > > this isn't a theoretical debate on why mysql performance might be slow. it > works fine on linux - our question is why we can't get that type of > performance out of freebsd. > > to reiterate for the nth time - i'm pledging $250 to whomever will own > this/fix it. i believe two other parties will pledge another combined $250 > as well. > > that's $500 to do something that [overall] benefits freebsd users, > especially those wishing to run high performance mysql servers on freebsd. > > we want it to at least match linux performance, if not be able to exceed > it. > > right now we're just going in loops with requests for more benchmarks and > such. if it's worth $500, someone "in the know" step up and we'll give you > access to one of our boxes, you can do whatever you want to get it to > perform how we'd like. at least 2 or 3 of us have pretty similarly > configured machines, so if you can get it to work good on one, that should > be able to be applied to all, if it's not a permanent obvious fix in the > freebsd kernel, scheduler, threading, or just a patch to get more out of > mysql on freebsd 5.x. There are people putting in a lot of time into locking down the kernel. We used to have people getting paid full-time to work on the kernel, but I don't think that's the case any longer (for certain, there are fewer of them). Unfortunately I don't think this is something you can throw a few hundred dollars at and get a 20 man-hour fix.