From owner-freebsd-current@FreeBSD.ORG Wed Sep 14 22:00:41 2005 Return-Path: X-Original-To: current@freebsd.org Delivered-To: freebsd-current@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 7859B16A424 for ; Wed, 14 Sep 2005 22:00:41 +0000 (GMT) (envelope-from lehmann@ans-netz.de) Received: from avocado.salatschuessel.net (avocado.salatschuessel.net [83.136.81.184]) by mx1.FreeBSD.org (Postfix) with ESMTP id 84D0C43D46 for ; Wed, 14 Sep 2005 22:00:39 +0000 (GMT) (envelope-from lehmann@ans-netz.de) Received: (qmail 5136 invoked by uid 89); 14 Sep 2005 21:59:18 -0000 Received: from unknown (HELO kartoffel.salatschuessel.net) (83.136.81.185) by avocado.salatschuessel.net with SMTP; 14 Sep 2005 21:59:18 -0000 Date: Thu, 15 Sep 2005 00:00:53 +0200 From: Oliver Lehmann To: joseph.koshy@gmail.com Message-Id: <20050915000053.448f251b.lehmann@ans-netz.de> In-Reply-To: <84dead72050914135239514c49@mail.gmail.com> References: <20050914194612.15692485.lehmann@ans-netz.de> <43286E37.40203@samsco.org> <20050914222013.178dc4dc.lehmann@ans-netz.de> <84dead72050914135239514c49@mail.gmail.com> X-Mailer: Sylpheed version 2.0.1 (GTK+ 2.6.10; amd64-portbld-freebsd6.0) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: current@freebsd.org Subject: Re: low(er) disk performance with sched_4bsd then with sched_ule X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 14 Sep 2005 22:00:41 -0000 Joseph Koshy wrote: > On -current you could use hwpmc and pmcstat to get a quick idea > of what is happening to the system: > > 1. # kldload hwpmc > You'll need a kernel compiled with options HWPMC_HOOKS. > > 2. # pmcstat -S instructions -c 1 -S instructions -O /tmp/ule.out dd if=...etc > > This command line instructs pmcstat to setup sampling > on both CPUs 0 & 1. > > 3. # pmcstat -R /tmp/ule.out -g > Convert the hwpmc(4) log to gprof gmon.out profiles. > > 4. # gprof -l /boot/kernel/kernel > ./k8-fr-retired-x86-instructions/kernel.gmon > gprof.ule > > Repeat for the 4BSD case and compare. > > Current has a few bug fixes that need to be merged to 6.0; > but you should get by in a pinch by copying over the content > of sys/dev/hwpmc/ and usr.sbin/pmcstat/ to a 6.x tree > and rebuilding. I did this now for bs=64k count=32000. The results are here: http://pofo.de/tmp/gprof.ule http://pofo.de/tmp/gprof.4bsd Hope this helps -- Oliver Lehmann http://www.pofo.de/ http://wishlist.ans-netz.de/