Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756212Ab1BICmO (ORCPT ); Tue, 8 Feb 2011 21:42:14 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:48114 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755930Ab1BICmM (ORCPT ); Tue, 8 Feb 2011 21:42:12 -0500 Date: Wed, 9 Feb 2011 03:41:44 +0100 From: Ingo Molnar To: Tim Bird Cc: "Rafael J. Wysocki" , Linus Torvalds , Mark Brown , Len Brown , Alan Stern , linux-pm@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Andrew Morton , Dmitry Torokhov , linux-embedded@vger.kernel.org, Thomas Gleixner Subject: Re: [PATCH] Remove CONFIG_PM altogether, enable power management all the time Message-ID: <20110209024144.GA32102@elte.hu> References: <1297081335-13631-1-git-send-email-broonie@opensource.wolfsonmicro.com> <201102072046.48763.rjw@sisk.pl> <20110207201803.GU10564@opensource.wolfsonmicro.com> <201102072215.59921.rjw@sisk.pl> <20110208122159.GA8284@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -2.0 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1742 Lines: 45 * Tim Bird wrote: > On Tue, Feb 8, 2011 at 4:21 AM, Ingo Molnar wrote: > > > Rafael, could you do a defconfig-ish x86 build with and without CONFIG_PM, and > > post the 'size vmlinux' comparison - so that we can see the size difference? We > > make some things CONFIG_EXPERT configurable just to enable folks who *really* > > want to cut down on kernel size to configure it out. > > I'm one of those people who *really* wants to cut down the kernel size. I've > recently worked on a product where the kernel RAM budget is ~1M. Did that kernel have CONFIG_PM disabled? > > Note that those usecases, even if they want a super-small kernel, might not care > > about PM at all while they care about size: small boot kernels in ROMs, or > > simple devices where CPU-idling implies deep low power mode, etc. > > So the vmlinux size comparisons would be needed really. If it's 5k nobody will > care. I care about 5K. (But honestly, I don't actively hunt stuff less than 10K > in size, because there's too many of them to chase, currently). The numbers that Frank Rowand sent show 40K+: | | For 2.6.38-rc4, x86_64, CONFIG_NR_CPUS=4: | | size vmlinux | text data bss dec hex filename | | 6553910 3555020 9994240 20103170 132c002 vmlinux with CONFIG_PM | 6512652 3553116 9994240 20060008 1321768 vmlinux without CONFIG_PM | | 41258 1904 0 43162 delta | Thanks, 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/