From owner-freebsd-stable@FreeBSD.ORG Mon Jun 20 11:14:57 2005 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id C76E916A41C for ; Mon, 20 Jun 2005 11:14:57 +0000 (GMT) (envelope-from markir@paradise.net.nz) Received: from linda-5.paradise.net.nz (bm-5a.paradise.net.nz [202.0.58.24]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8B07943D1F for ; Mon, 20 Jun 2005 11:14:55 +0000 (GMT) (envelope-from markir@paradise.net.nz) Received: from smtp-1.paradise.net.nz (smtp-1a.paradise.net.nz [202.0.32.194]) by linda-5.paradise.net.nz (Paradise.net.nz) with ESMTP id <0IID00842R8SFX@linda-5.paradise.net.nz> for freebsd-stable@freebsd.org; Mon, 20 Jun 2005 23:14:52 +1200 (NZST) Received: from [192.168.1.11] (218-101-45-99.paradise.net.nz [218.101.45.99]) by smtp-1.paradise.net.nz (Postfix) with ESMTP id C0CFE82912; Mon, 20 Jun 2005 23:14:51 +1200 (NZST) Date: Mon, 20 Jun 2005 23:14:48 +1200 From: Mark Kirkwood In-reply-to: <1dbad315050620034565892ee@mail.gmail.com> To: Michael Schuh Message-id: <42B6A528.2000204@paradise.net.nz> MIME-version: 1.0 Content-type: text/plain; format=flowed; charset=ISO-8859-1 Content-transfer-encoding: 7bit X-Accept-Language: en-us, en User-Agent: Mozilla Thunderbird 1.0.2 (X11/20050511) References: <1dbad315050620034565892ee@mail.gmail.com> Cc: freebsd-stable@freebsd.org Subject: Re: FreeBSD MySQL still WAY slower than Linux X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 20 Jun 2005 11:14:57 -0000 Michael Schuh wrote: > > > My results was that RELENG_5 is half as RELENG_4 fast by disk-access > (ata-related). > > I have seen that RELENG_5 with GENERIC Kernel and only modified option HZ=2000. > > the spread begind with Gentoo (mentoided from me as the slowest, but > errare humanum est) > > Gentoo : 100% time consumption > RELENG_4: 67% time consumtion > DrangonFly Rel1.2 69-72% time consumption (i think preemtion) > RELENG_5 134% time consumtion > > these tests are made on physically the same Hardware (real, not equal > system, same system, same disk, same RAM) with the command: > > # cd /; /usr/bin/time dd if=/dev/zero bs=1024 count=1024k of=zerofile; > > You have shown that sequential IO is slower in RELENG_5 (I think others have observed this also - check out Google)...However, random IO is often more important for databases, and RELENG_5 can be faster than RELENG_4 (try out iozone, it makes testing this easy). Also note that if your operating systems are installed in different parts of the same disk, then this will effect your results too - as some parts are faster than others. With respect to Mysql performance, I would suspect threading or threading/kernel interaction as the culprit. (That reminds me, I don't recall seeing the original poster re-doing the tests with 6.0-CURRENT - that would be interesting). cheers Mark