From owner-freebsd-current@FreeBSD.ORG Wed Nov 2 15:23:52 2005 Return-Path: X-Original-To: freebsd-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 E638D16A421; Wed, 2 Nov 2005 15:23:51 +0000 (GMT) (envelope-from ticso@cicely12.cicely.de) Received: from ant.bwct.de (ant.bwct.de [85.159.14.68]) by mx1.FreeBSD.org (Postfix) with ESMTP id EBEA643D48; Wed, 2 Nov 2005 15:23:37 +0000 (GMT) (envelope-from ticso@cicely12.cicely.de) Received: from cicely5.cicely.de ([10.1.1.7]) by ant.bwct.de (8.12.11/8.12.11) with ESMTP id jA2FNUmv000589; Wed, 2 Nov 2005 16:23:33 +0100 (CET) Received: from cicely12.cicely.de (cicely12.cicely.de [10.1.1.14]) by cicely5.cicely.de (8.13.4/8.13.4) with ESMTP id jA2FNQU2080328 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 2 Nov 2005 16:23:26 +0100 (CET) (envelope-from ticso@cicely12.cicely.de) Received: from cicely12.cicely.de (localhost [127.0.0.1]) by cicely12.cicely.de (8.13.4/8.13.3) with ESMTP id jA2FNPdL093838; Wed, 2 Nov 2005 16:23:25 +0100 (CET) (envelope-from ticso@cicely12.cicely.de) Received: (from ticso@localhost) by cicely12.cicely.de (8.13.4/8.13.3/Submit) id jA2FNNAM093837; Wed, 2 Nov 2005 16:23:23 +0100 (CET) (envelope-from ticso) Date: Wed, 2 Nov 2005 16:23:23 +0100 From: Bernd Walter To: Gavin Atkinson Message-ID: <20051102152322.GF93549@cicely12.cicely.de> References: <1130943516.51544.34.camel@buffy.york.ac.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1130943516.51544.34.camel@buffy.york.ac.uk> X-Operating-System: FreeBSD cicely12.cicely.de 5.4-STABLE alpha User-Agent: Mutt/1.5.9i X-Spam-Status: No, score=-5.9 required=5.0 tests=ALL_TRUSTED,BAYES_00 autolearn=ham version=3.0.4 X-Spam-Report: * -3.3 ALL_TRUSTED Did not pass through any untrusted hosts * -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1% * [score: 0.0000] X-Spam-Checker-Version: SpamAssassin 3.0.4 (2005-06-05) on cicely12.cicely.de Cc: freebsd-current@freebsd.org, rwatson@freebsd.org Subject: Re: Poor NFS server performance in 6.0 with SMP and mpsafenet=1 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: ticso@cicely.de List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 02 Nov 2005 15:23:52 -0000 On Wed, Nov 02, 2005 at 02:58:36PM +0000, Gavin Atkinson wrote: > Hi, > > I'm seeing incredibly poor performance when serving files from an SMP > FreeBSD 6.0RC1 server to a Solaris 10 client. I've done some > experimenting and have discovered that either removing SMP from the > kernel, or setting debug.mpsafenet=0 in loader.conf massively improves > the speed. Switching preemption off seems to also help. > > A quick summary of my findings: switching SMP off and setting > mpsafenet=0 gives more than 700% boost in performance. PREEMPTION is a > pessimisation in the SMP case, mpsafenet=1 is a pessimisation in all > cases. Given these are three of the major new features in 6.0, this > doesn't seem ideal :) > > The following are average times, in seconds, to serve a 512meg file over > NFS to the Solaris host. Each experiment was performed immediately > after a reboot of the FreeBSD host, and after one untimed transfer (in > order to warm the FreeBSD vfs cache). > > No SMP, mpsafenet=1 59.4 > No SMP, mpsafenet=0 49.4 > No SMP, mpsafenet=1, no PREEMPTION 53.1 > No SMP, mpsafenet=0, no PREEMPTION 51.9 > SMP, mpsafenet=1 351.7 > SMP, mpsafenet=0 74.5 > SMP, mpsafenet=1, no PREEMPTION 264.9 > SMP, mpsafenet=0, no PREEMPTION 53.7 Which scheduler? -- B.Walter BWCT http://www.bwct.de bernd@bwct.de info@bwct.de