Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751674Ab0AJENN (ORCPT ); Sat, 9 Jan 2010 23:13:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751136Ab0AJENM (ORCPT ); Sat, 9 Jan 2010 23:13:12 -0500 Received: from casper.infradead.org ([85.118.1.10]:44503 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751062Ab0AJENM (ORCPT ); Sat, 9 Jan 2010 23:13:12 -0500 Date: Sat, 9 Jan 2010 20:15:27 -0800 From: Arjan van de Ven To: Ray Lee Cc: Dimitrios Apostolou , Alex Chiang , Len Brown , Bjorn Helgaas , Andrew Morton , Yinghai Lu , linux-kernel@vger.kernel.org Subject: Re: High cpu temperature with 2.6.32, bisection shows commit 69d258 (fwd) Message-ID: <20100109201527.77dd1714@infradead.org> In-Reply-To: <2c0942db1001091807k542b1052s96111775d6431bd0@mail.gmail.com> References: <20100108171513.GB22713@ldl.fc.hp.com> <20100109134352.3dedd4ea@infradead.org> <20100109160836.26a344a9@infradead.org> <20100109164240.43b21247@infradead.org> <2c0942db1001091807k542b1052s96111775d6431bd0@mail.gmail.com> Organization: Intel X-Mailer: Claws Mail 3.7.3 (GTK+ 2.16.6; i586-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1345 Lines: 35 On Sat, 9 Jan 2010 18:07:14 -0800 Ray Lee wrote: > On Sat, Jan 9, 2010 at 4:42 PM, Arjan van de Ven > wrote: > > basically it appears that your machine, when the kernel asks for C2, > > exits C2 immediately again. > > > > The old algorithm somehow caught this and stopped asking for C2 > > most of the time; the new algorithm doesn't see any activity and > > asks for C2 again. > > This change of behavior will certainly bite more users out there. Is > there any way we can detect the systems that aren't honoring the C2 > request and limit back to C1? it's not very likely that there are many such systems; it takes work to break C2.... so far in 6 months 2 systems showed up, and this includes a fedora release. on the other hand, it's not so easy to detect the situation; exiting c2 quickly can also happen in normal use, so we'd have to have some sort of threshold, which will be fragile by itself. -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/