Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752187Ab0AAXMN (ORCPT ); Fri, 1 Jan 2010 18:12:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752059Ab0AAXMM (ORCPT ); Fri, 1 Jan 2010 18:12:12 -0500 Received: from casper.infradead.org ([85.118.1.10]:33286 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752038Ab0AAXML (ORCPT ); Fri, 1 Jan 2010 18:12:11 -0500 Date: Fri, 1 Jan 2010 15:14:37 -0800 From: Arjan van de Ven To: "Smith, GeoffX" Cc: "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] proc: Get/set timer slack through /proc Message-ID: <20100101151437.17834b25@infradead.org> In-Reply-To: <354B2877CF17F44BB3FA44EB4DB0E5470C91CE1D19@orsmsx510.amr.corp.intel.com> References: <354B2877CF17F44BB3FA44EB4DB0E5470C91CE1D19@orsmsx510.amr.corp.intel.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: 1406 Lines: 35 On Thu, 31 Dec 2009 13:01:49 -0800 "Smith, GeoffX" wrote: > Subject: Get/set timer_slack_ns through /proc > > This patch makes the timer_slack_ns parameter accessible through > the /proc system. > > On 9/1/2008, arjan@linux.intel.com submitted a patch to allow a > process to set the timer slack value as part of the range timers > feature. Further, he noted that "Applications and admins can > override this [the timer slack value] via the prctl()." > > We have found this feature useful in attempting to reduce system > wakeups caused by timer interrupts. But we have also found that > while applications can set their own timer slack value, there is no > provision for setting the timer slack for another process -- prctl() > only operates on the current process. > this statement is incorrect btw; timerslack is explicitly inherited over exec, so you can have (and we do have) a utility similar to the nice program, that launches an application with a specific timer slack. -- 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/