From owner-freebsd-questions Thu Jan 4 6:55:15 2001 From owner-freebsd-questions@FreeBSD.ORG Thu Jan 4 06:55:13 2001 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mail2.bna.bellsouth.net (mail2.bna.bellsouth.net [205.152.150.14]) by hub.freebsd.org (Postfix) with ESMTP id A1EFE37B402 for ; Thu, 4 Jan 2001 06:55:12 -0800 (PST) Received: from planetwe.com (adsl-20-109-209.bna.bellsouth.net [66.20.109.209]) by mail2.bna.bellsouth.net (3.3.5alt/0.75.2) with ESMTP id JAA00427; Thu, 4 Jan 2001 09:31:02 -0500 (EST) Message-ID: <3A548917.2020403@planetwe.com> Date: Thu, 04 Jan 2001 08:30:47 -0600 From: Drew Sanford User-Agent: Mozilla/5.0 (X11; U; Linux 2.2.12 i386; en-US; m18) Gecko/20001107 Netscape6/6.0 X-Accept-Language: en MIME-Version: 1.0 To: Michael Wells Cc: freebsd-questions@freebsd.org Subject: Re: SMP kernel overheats References: <20010104102301.B13113@imap.cam.zeus.co.uk> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Michael, I'll take a shot at this for you. I believe that the reason for this is that SMP kernels do not currently use the hlt instruction to stop the cpu, there is simply an idle process that runs the cpu's wide open all the time. Top apparently takes the amount of cpu time that process gets into account when it looks at the system load, etc. Again, I'm not certain I'm right about this, but you may be able to verify it by doing something like loading linux and running an RC5 client on the machine and seeing if it does the same thing. There may be a guru out there calling me stupid right now - If I'm wrong, let me know:) Michael Wells wrote: > Hi all, > > I've been going through a kernel configuration for my SMP machine. It's > a Gigabyte 6BXD with 2xPIII 550MHz processors. I can provide other > information if necessary about the hardware, but it's nothing too exotic. > > The problem I'm having is that although the kernel seems to work fine, > and tools like "top" report that the CPUs are idleing, after a few minutes > the system starts getting really warm, and eventually the BIOS thermal > alarms are triggered at 65 degrees C. As I say, despite this it is all > fine in operation, and processes on both CPUs are ok. It is clearly > running way too hot though. > > I've checked my hardware out, and it's all ok. It's working cool in > Linux, so I think there's something in my kernel that I need to sort > out. > > What I was wondering was is this a known problem? Can it be fixed? Any > other ideas? Thanks, your help is much appreciated. > > Cheers > Michael Wells > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-questions" in the body of the message To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message