Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756182Ab0FSOzR (ORCPT ); Sat, 19 Jun 2010 10:55:17 -0400 Received: from casper.infradead.org ([85.118.1.10]:46171 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756111Ab0FSOzP (ORCPT ); Sat, 19 Jun 2010 10:55:15 -0400 Date: Sat, 19 Jun 2010 07:54:51 -0700 From: Arjan van de Ven To: Andi Kleen Cc: Tejun Heo , mingo@elte.hu, tglx@linutronix.de, bphilips@suse.de, yinghai@kernel.org, akpm@linux-foundation.org, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, jeff@garzik.org, linux-ide@vger.kernel.org, stern@rowland.harvard.edu, gregkh@suse.de, khali@linux-fr.org Subject: Re: [PATCH 09/12] irq: implement IRQ expecting Message-ID: <20100619075451.48c13589@infradead.org> In-Reply-To: <20100619090031.GE18946@basil.fritz.box> References: <1276443098-20653-1-git-send-email-tj@kernel.org> <1276443098-20653-10-git-send-email-tj@kernel.org> <20100616204854.4b036f87@infradead.org> <87zkyro1xl.fsf@basil.nowhere.org> <4C1C830B.5020806@kernel.org> <20100619090031.GE18946@basil.fritz.box> 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 Content-Length: 1073 Lines: 29 On Sat, 19 Jun 2010 11:00:31 +0200 Andi Kleen wrote: > > IIUC, it's not to help or optimize polling itself. It just gives > > us a way to estimate when the next interrupt would be so that power > > can be optimized for non polling cases. > > Shouldn't the idle governour estimate this already? we have a set of heuristics in the idle governor to try to predict the future. For patterns that are regular in some shape of form we can do this. Here we have the opportunity to get real good information.. we KNOW now an interrupt is coming, and we can even estimate how long it'll be... Even for the first few after a long time, before a pattern emerges. -- 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/