From owner-freebsd-performance@FreeBSD.ORG Wed Oct 24 15:59:46 2007 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id CD73016A46E; Wed, 24 Oct 2007 15:59:46 +0000 (UTC) (envelope-from nevans@talkpoint.com) Received: from mailbox.talkpoint.com (mailbox.talkpoint.com [204.141.15.162]) by mx1.freebsd.org (Postfix) with ESMTP id 03C8D13C48D; Wed, 24 Oct 2007 15:59:45 +0000 (UTC) (envelope-from nevans@talkpoint.com) Received: from localhost (localhost [127.0.0.1]) by mailbox.talkpoint.com (Postfix) with ESMTP id 73CE7458004; Wed, 24 Oct 2007 11:35:17 -0400 (EDT) X-Virus-Scanned: amavisd-new at X-Spam-Flag: NO X-Spam-Score: -2.43 X-Spam-Level: X-Spam-Status: No, score=-2.43 tagged_above=-10 required=5 tests=[AWL=0.169, BAYES_00=-2.599] Received: from mailbox.talkpoint.com ([127.0.0.1]) by localhost (mailbox.talkpoint.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id KTwF4uFmCCrR; Wed, 24 Oct 2007 11:35:15 -0400 (EDT) Received: from pleiades.nextvenue.com (pleiades.nextvenue.com [204.141.15.194]) by mailbox.talkpoint.com (Postfix) with ESMTP id 1739C458001; Wed, 24 Oct 2007 11:35:15 -0400 (EDT) Date: Wed, 24 Oct 2007 11:34:34 -0400 From: Nick Evans To: josh.carroll@gmail.com Message-ID: <20071024113434.326c3749@pleiades.nextvenue.com> In-Reply-To: <8cb6106e0710240639r20e03ce9w81ed3354338b7395@mail.gmail.com> References: <8cb6106e0710230902x4edf2c8eu2d912d5de1f5d4a2@mail.gmail.com> <471E343C.2040509@FreeBSD.org> <20071024171915.E84143@delplex.bde.org> <8cb6106e0710240639r20e03ce9w81ed3354338b7395@mail.gmail.com> X-Mailer: Claws Mail 2.8.0 (GTK+ 2.10.9; i386-portbld-freebsd7.0) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: remy.nonnenmacher@activnetworks.com, Kris Kennaway , freebsd-performance@freebsd.org, Bruce Evans Subject: Re: ULE vs. 4BSD in RELENG_7 X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 24 Oct 2007 15:59:46 -0000 On Wed, 24 Oct 2007 09:39:29 -0400 "Josh Carroll" wrote: > > 5-6% is a lot. ULE has some tuning for makeworld in -current, which > > for me reduced it to less than 1% slower than 4BSD (down from 5-10% > > slower), for the case of makeworld -j4 over nfs on a 2-CPU system with > > the sources pre-cached on the server and objects on a local file system, > > and extensive local tuning of makeworld, nfs and network drivers. I > > think the tuning in ULE was mainly for a 2-CPU system, because makeworld > > seemed to be very bad under ULE only with 2 CPUs. Apparently, it is also > > very bad with more CPUs. There are sysctls to modify the ULE tuning. > > I found Kris' document here: > > http://people.freebsd.org/~kris/scaling/mysql.html > > Which also mentions some ULE tuning. The sched_ule man page doesn't > mention what these are. Can someone point me to a document that > explains the sysctl tuning I can try? > > I imagine I would want to tweak one or more of these: > > kern.sched.preemption: 1 > kern.sched.topology: 0 > kern.sched.steal_thresh: 2 > kern.sched.steal_idle: 1 > kern.sched.steal_htt: 1 > kern.sched.balance_interval: 133 > kern.sched.balance: 1 > kern.sched.tryself: 1 > kern.sched.affinity: 3 > kern.sched.pick_pri: 1 > kern.sched.preempt_thresh: 64 > kern.sched.interact: 30 > kern.sched.slice: 13 > > But I'm not sure which to try. I did try setting kern.sched.pick_pri > to 0, but that hasn't helped the ffmpeg workload at least. > > Thanks, > Josh > _______________________________________________ > freebsd-performance@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-performance > To unsubscribe, send any mail to > "freebsd-performance-unsubscribe@freebsd.org" kern.sched.steal_thresh is/was one of the more effective tuning sysctls. rev 1.205 of sched_ule had a change that was supposed to automatically adjust it based on the number of cores. Is this the same 8 core system as the other thread? In that case the commit dictates steal_thresh should be set to 3. Give that a try. Nick