From owner-freebsd-smp Sat Aug 26 3:17:13 2000 Delivered-To: freebsd-smp@freebsd.org Received: from verdi.nethelp.no (verdi.nethelp.no [158.36.41.162]) by hub.freebsd.org (Postfix) with SMTP id 00B7537B423 for ; Sat, 26 Aug 2000 03:17:10 -0700 (PDT) Received: (qmail 54236 invoked by uid 1001); 26 Aug 2000 10:17:08 +0000 (GMT) To: j.saito@wanadoo.fr Cc: freebsd-smp@FreeBSD.ORG Subject: Re: unusually high temperature with smp kernel on ABit BP6 From: sthaug@nethelp.no In-Reply-To: Your message of "Sat, 26 Aug 2000 11:50:01 +0200 (CEST)" References: X-Mailer: Mew version 1.05+ on Emacs 19.34.2 Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Date: Sat, 26 Aug 2000 12:17:08 +0200 Message-ID: <54234.967285028@verdi.nethelp.no> Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > The motherboard temperature keeps getting higher (easily reaching over > 50°C in some minutes) after booting when a smp kernel is loaded, even if > the machine is almost 100% idle. With an up kernel, the temperature gets > down to under 40°C some minutes after the booting. This was discussed extensively a couple of months ago, and as far as I remember no completely satisfactory solution was identified. The problem is that the UP code halts the CPU when it is idle, while SMP code does not. I (and several others) have been running with the following simple patch to /sys/i386/i386/swtch.s. It seems to do the job here. Steinar Haug, Nethelp consulting, sthaug@nethelp.no ---------------------------------------------------------------------- *** swtch.s.orig Sun Jan 2 22:36:22 2000 --- swtch.s Sun May 14 12:19:00 2000 *************** *** 251,259 **** ENTRY(default_halt) sti ! #ifndef SMP hlt /* XXX: until a wakeup IPI */ ! #endif ret /* --- 251,259 ---- ENTRY(default_halt) sti ! /* #ifndef SMP */ hlt /* XXX: until a wakeup IPI */ ! /* #endif */ ret /* To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message