Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751378AbVK2Pmp (ORCPT ); Tue, 29 Nov 2005 10:42:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751386AbVK2Pmp (ORCPT ); Tue, 29 Nov 2005 10:42:45 -0500 Received: from ms-smtp-04.nyroc.rr.com ([24.24.2.58]:59068 "EHLO ms-smtp-04.nyroc.rr.com") by vger.kernel.org with ESMTP id S1751384AbVK2Pmo (ORCPT ); Tue, 29 Nov 2005 10:42:44 -0500 Subject: Re: [RFC][PATCH] Runtime switching of the idle function [take 2] From: Steven Rostedt To: Andi Kleen Cc: Ingo Molnar , acpi-devel@lists.sourceforge.net, len.brown@intel.com, nando@ccrma.Stanford.EDU, rlrevell@joe-job.com, linux-kernel@vger.kernel.org, paulmck@us.ibm.com, kr@cybsft.com, tglx@linutronix.de, pluto@agmk.net, john.cooper@timesys.com, bene@linutronix.de, dwalker@mvista.com, trini@kernel.crashing.org, george@mvista.com, akpm@osdl.org In-Reply-To: <20051129145022.GE19515@wotan.suse.de> References: <20051124150731.GD2717@elte.hu> <1132952191.24417.14.camel@localhost.localdomain> <20051126130548.GA6503@elte.hu> <1133232503.6328.18.camel@localhost.localdomain> <20051128190253.1b7068d6.akpm@osdl.org> <1133235740.6328.27.camel@localhost.localdomain> <20051128200108.068b2dcd.akpm@osdl.org> <20051129064420.GA15374@elte.hu> <1133273971.6328.49.camel@localhost.localdomain> <20051129145022.GE19515@wotan.suse.de> Content-Type: text/plain Date: Tue, 29 Nov 2005 10:42:34 -0500 Message-Id: <1133278954.6328.59.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 958 Lines: 22 On Tue, 2005-11-29 at 15:50 +0100, Andi Kleen wrote: > On Tue, Nov 29, 2005 at 09:19:31AM -0500, Steven Rostedt wrote: > > > And in practice the CPU will run so hot that only benchmarkers like it. > > > > Why would it run hot? What's the difference between polling and doing > > other things. How many transistors does it take to poll? > > It will prevent the CPU from going into sleep states and essentially > keep most of it enabled. Well, there's one thing that my patch _does_ help with. (And it has just helped me now). If you boot up with idle=poll and forget about it, you can check what idle routine is being used and switch out of poll without rebooting. (like I'm doing right now :-) -- Steve - 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/