Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754094AbWKGIIb (ORCPT ); Tue, 7 Nov 2006 03:08:31 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754106AbWKGIIb (ORCPT ); Tue, 7 Nov 2006 03:08:31 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:19884 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S1754094AbWKGIIa (ORCPT ); Tue, 7 Nov 2006 03:08:30 -0500 Date: Tue, 7 Nov 2006 09:07:33 +0100 From: Ingo Molnar To: Len Brown Cc: Andreas Mohr , Thomas Gleixner , linux-kernel@vger.kernel.org Subject: Re: CONFIG_NO_HZ: missed ticks, stall (keyb IRQ required) [2.6.18-rc4-mm1] Message-ID: <20061107080733.GB9910@elte.hu> References: <20061101140729.GA30005@rhlx01.hs-esslingen.de> <1162830033.4715.201.camel@localhost.localdomain> <20061106205825.GA26755@rhlx01.hs-esslingen.de> <200611070141.16593.len.brown@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200611070141.16593.len.brown@intel.com> User-Agent: Mutt/1.4.2.2i X-ELTE-SpamScore: -2.8 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.8 required=5.9 tests=ALL_TRUSTED,AWL,BAYES_50 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts 0.5 BAYES_50 BODY: Bayesian spam probability is 40 to 60% [score: 0.5000] -0.0 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1026 Lines: 23 * Len Brown wrote: > So given that C3 on every known system that has shipped to date breaks > the LAPIC timer (and apparently this applies to C2 on these AMD > boxes), dynticks needs a solid story for co-existing with C3. check out 2.6.19-rc4-mm2: it detects this breakage and works it around by using the PIT as a clock-events source. That did the trick on my laptop which has this problem too. I agree with you that degrading the powersaving mode is not an option. we've got a question about HPET: it seems all recent hardware has it, but the BIOS rarely mentions it, so the Linux driver does not enable HPET. Is there any chance to enable HPET (in the chipset?) - this would probably be a higher-quality clock-events source than the PIT. Ingo - 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/