From owner-freebsd-stable@FreeBSD.ORG Thu Jun 7 01:01:11 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id AC019106566C for ; Thu, 7 Jun 2012 01:01:11 +0000 (UTC) (envelope-from momchil@xaxo.eu) Received: from vps2.xaxo.eu (vps2.xaxo.eu [78.47.156.66]) by mx1.freebsd.org (Postfix) with ESMTP id 3E3D68FC19 for ; Thu, 7 Jun 2012 01:01:11 +0000 (UTC) Received: from t61.xaxo.eu ([10.75.23.6]) by vps2.xaxo.eu (8.14.4/8.14.4) with ESMTP id q57017uu068794; Thu, 7 Jun 2012 02:01:07 +0200 (CEST) (envelope-from momchil@xaxo.eu) Date: Thu, 07 Jun 2012 03:01:07 +0200 Message-ID: <86fwa8szos.wl%momchil@xaxo.eu> From: =?UTF-8?B?0JzQvtC80YfQuNC7INCY0LLQsNC90L7Qsg==?= To: freebsd-stable@freebsd.org MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Subject: ULE Scheduler X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 07 Jun 2012 01:01:11 -0000 Hi, today I had a really strange experience with my laptop. I ran 2 lisp processes each consuming 100% CPU (i.e. in top, 100% CPU means one full core), since I have 2 cores, it means full processor load. I was moreover running Emacs and Opera, but that is more or less irrelevant since they consume negligible amount of CPU time. At some point my Xorg died and I was dropped in the terminal and the first thought through my mind was that my laptop just said "goodbye, it was nice meeting you after 4+ years". A second later I saw: Jun 7 01:00:06 t61 kernel: acpi_tz1: WARNING - current temperature (100.1C) exceeds safe limits which was a sign of relief: "oh, maybe the fan got busted...". So I took a screw driver and disassembled my Lenovo T61. Cleaning all the dust and putting a fresh amount of thermal fluid (did it 1 year ago), I booted again and started both processes again and took a look at the temperature. It was constantly increasing from about 33 C. I took a look at top and saw that both processes were wildly jumping accross the cores, i.e. CPU0 and CPU1. So before reading all the papers about the ULE scheduler and the source code, I would like to as a simple question: is it that stupid? I mean, there are just 2 processes running (except of top, X and ... which should be scheduled occasionally) on 2 cores of one physical processor. Why sould each be scheduled on a different core each time? I did cpuset to pin each to a specific core and got to about a constant temperature of 72 C. I am affraid to "cpuset -l 0,1 -p <...>" both of them since I might again get at 100 C. Is there some remedy? Please CC me, since I am not subscribed to the list. Regards, Momchil