From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756412Ab0GHPH0 (ORCPT ); Thu, 8 Jul 2010 11:07:26 -0400 Received: from casper.infradead.org ([85.118.1.10]:49157 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754718Ab0GHPHY (ORCPT ); Thu, 8 Jul 2010 11:07:24 -0400 Date: Thu, 8 Jul 2010 08:11:08 -0700 From: Arjan van de Ven To: Peter Zijlstra Cc: Norbert Preining , linux-kernel@vger.kernel.org, Ingo Molnar , akpm Subject: Re: high power consumption in recent kernels Message-ID: <20100708081108.43268bee@infradead.org> In-Reply-To: <1278590303.1900.91.camel@laptop> References: <20100706164539.GA14783@gamma.logic.tuwien.ac.at> <1278579992.1900.17.camel@laptop> <20100708045711.398d4e26@infradead.org> <1278590303.1900.91.camel@laptop> Organization: Intel X-Mailer: Claws Mail 3.7.6 (GTK+ 2.20.1; i386-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 > and for that matter, what is "[extra timer interrupt]", surely the > timer hardware doesn't generate spurious interrupts? extra timer interrupt are those cases where we see the hardware interrupt fire, but we do not have software timers to account for them. two cases this can happen * a NO_HZ bug * we are idle longer than the longest interval we can program the hw timer for. Without HPET this can happen. -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org