From owner-freebsd-questions@FreeBSD.ORG Wed Jan 12 02:10:02 2005 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 38A0D16A4CE for ; Wed, 12 Jan 2005 02:10:02 +0000 (GMT) Received: from smtp.knology.net (smtp.knology.net [24.214.63.101]) by mx1.FreeBSD.org (Postfix) with SMTP id A0A4C43D58 for ; Wed, 12 Jan 2005 02:10:01 +0000 (GMT) (envelope-from dkelly@HiWAAY.net) Received: (qmail 9633 invoked by uid 0); 12 Jan 2005 02:09:43 -0000 Received: from user-69-73-60-132.knology.net (HELO ?10.0.0.68?) (69.73.60.132) by smtp1.knology.net with SMTP; 12 Jan 2005 02:09:43 -0000 In-Reply-To: <9094-SnapperMsgD246FC56BE0A255B@68.243.126.247> References: <9094-SnapperMsgD246FC56BE0A255B@68.243.126.247> Mime-Version: 1.0 (Apple Message framework v619) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: <0D509666-643F-11D9-A9EF-000393BB56F2@HiWAAY.net> Content-Transfer-Encoding: 7bit From: David Kelly Date: Tue, 11 Jan 2005 20:09:55 -0600 To: "Timothy J. Luoma" X-Mailer: Apple Mail (2.619) cc: freebsd-questions@freebsd.org Subject: Re: Hyperthreading hurts 5.3? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 12 Jan 2005 02:10:02 -0000 On Jan 11, 2005, at 6:52 PM, Timothy J. Luoma wrote: > summary: should I disable hypertheading in the BIOS when running 5.3? > > Background info: > > I have a new Dell Dimension 3000 running 5.3. > > I noticed some huge pauses when copying a large # of files across the > network. Googling around found some information about earlier > versions of > 5.x and Hyperthreading being detrimenatl for performance. > > Whether or not it was the source of the network copy problem, I am > trying > to decide if I should disable Hyperthreading. IMO there are times where 5.3 doesn't schedule the CPU as fairly as one would like. Times I've suspected this were during aggressive file activity on a few large files. I have HT disabled due to earlier problems with the combination of SATA and vinum resulting in a trashed fs with a late version of 5.2.1. The benefits of HT are too few for me to risk trashing the fs now its full. If you can reproduce your situation then I suggest disabling HT and see what happens. That's the only way anybody would know if HT is part of the problem or part of the solution. > Iif YES, I wasn't clear if people meant "disable in BIOS" or just some > configuration setting in a *.conf file. In the BIOS. > (disabling HT will apparently mean I have to reinstall XP on the other > drive. What does XP have to do with it? IIRC on Dell its F2 during the power-on diagnostics to reach the built-in BIOS config. That is where HT is to be disabled. Works exactly that way on my PowerEdge 400SC 2.8G P4. The only question is whether the key is F2 to get there or not. Was F2 this afternoon on my ancient Dell Optiplex 450 MHz P2 when I had to boot a DOS floppy to remap some bad blocks. -- David Kelly N4HHE, dkelly@HiWAAY.net ======================================================================== Whom computers would destroy, they must first drive mad.