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
On 06/06/2012 18:01, ?????? ?????? wrote:> Is there some remedy?Try the 4BSD scheduler. -- This .signature sanitized for your protection
Hi, On 07 June 2012 3:01:07 ?????? ?????? wrote:> 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?maybe, maybe not. It could be that the difference is minor as the cache for both kernels is in the same chip.> > 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.This would be the interesting point? Did it happen because of the dirt or because or the scheduler.> > Is there some remedy?I think that the only remedy available is the one you applied. Erich
Am Thu, 07 Jun 2012 03:01:07 +0200 schrieb ?????? ?????? <momchil@xaxo.eu>:> Is there some remedy?Hi, I remember this series, I've had a T60p and when I compiled world, I placed a fan in front of it to cool it down from 100?C. The difference with T60p was that it simply shut off reaching 101?C. The problem is the hardware, not FreeBSD. T60p and obviously T60, too, was made by some crazy people who had the idea to cool the CPU und the GPU under the same heat sink. The funny thing is that the GPU is running at 70?C all the time, because FreeBSD does not implement voltage regulation for the VGA chipset. The result is that the GPU warms up the CPU to at least 55?C while idle. If you want to have a cooler CPU implement power saving for the Radeon chipset there. Martin -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 834 bytes Desc: not available Url : http://lists.freebsd.org/pipermail/freebsd-stable/attachments/20120607/c0516ffd/signature.pgp