From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932179AbWGaTf2 (ORCPT ); Mon, 31 Jul 2006 15:35:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932190AbWGaTf2 (ORCPT ); Mon, 31 Jul 2006 15:35:28 -0400 Received: from outpost.ds9a.nl ([213.244.168.210]:56806 "EHLO outpost.ds9a.nl") by vger.kernel.org with ESMTP id S932179AbWGaTf1 (ORCPT ); Mon, 31 Jul 2006 15:35:27 -0400 Date: Mon, 31 Jul 2006 21:35:07 +0200 From: bert hubert To: Robert Hancock Cc: David Rees , Arjan van de Ven , Tomasz Torcz , linux-kernel@vger.kernel.org, zwane@arm.linux.org.uk Subject: Re: 2.6.18 regression: cpufreq broken since 2.6.18-rc1 on pentium4 Message-ID: <20060731193507.GC16797@outpost.ds9a.nl> Mail-Followup-To: bert hubert , Robert Hancock , David Rees , Arjan van de Ven , Tomasz Torcz , linux-kernel@vger.kernel.org, zwane@arm.linux.org.uk References: <44CE567D.40305@shaw.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <44CE567D.40305@shaw.ca> User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 31, 2006 at 01:14:05PM -0600, Robert Hancock wrote: > per watt. As well, when the CPU has nothing to do it will be halted > anyway which does pretty much the same as what clockmod is doing. You are empirically wrong in my case. I can't make you hear the difference in noise, but perhaps this will convince you: $ sensors | grep CPU CPU_Fan: 2359 RPM (min = 4000 RPM) CPU: +61 C (low = +10 C, high = +50 C) $ sudo /etc/init.d/powernowd start * Starting powernowd... [ ok ] $ sensors | grep CPU CPU_Fan: 1411 RPM (min = 4000 RPM) CPU: +57 C (low = +10 C, high = +50 C) $ sudo /etc/init.d/powernowd stop * Stopping powernowd: [ ok ] $ sensors | grep CPU CPU_Fan: 2452 RPM (min = 4000 RPM) CPU: +61 C (low = +10 C, high = +50 C) And this with only seconds in between starting and stopping, on an idle system. > Essentially clockmod is there as a way to limit the thermal output of > the CPU in thermal emergencies, it's not really very good as a > power-saving feature. That I've measured, and indeed, the same amount of power is drawn from the mains. But the reduction in fan noise is worth it. On this CPU, HLT may simply not be doing as good a job. Who knows. processor : 0 vendor_id : GenuineIntel cpu family : 15 model : 4 model name : Intel(R) Pentium(R) 4 CPU 3.00GHz stepping : 1 cpu MHz : 3000.000 cache size : 1024 KB It does reduce effective CPU to 300MHz though, which is a lot. Kind regards, bert -- http://www.PowerDNS.com Open source, database driven DNS Software http://netherlabs.nl Open and Closed source services