Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754540AbXFYA7W (ORCPT ); Sun, 24 Jun 2007 20:59:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751934AbXFYA7O (ORCPT ); Sun, 24 Jun 2007 20:59:14 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:41511 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751850AbXFYA7O (ORCPT ); Sun, 24 Jun 2007 20:59:14 -0400 Subject: Re: -Os versus -O2 From: Arjan van de Ven To: Adrian Bunk Cc: Benjamin LaHaise , Oleg Verych , rae l , linux-kernel@vger.kernel.org In-Reply-To: <20070625004106.GA1094@stusta.de> References: <467cac85.081b600a.5b88.457f@mx.google.com> <91b13c310706240558p70dbaed2g570b57ab480aa974@mail.gmail.com> <20070624222518.GA10398@flower.upol.cz> <1182723318.6819.5.camel@laptopd505.fenrus.org> <20070624232314.GA971@kvack.org> <1182730156.6819.8.camel@laptopd505.fenrus.org> <20070625001203.GB971@kvack.org> <1182731022.6819.10.camel@laptopd505.fenrus.org> <20070625004106.GA1094@stusta.de> Content-Type: text/plain Organization: Intel International BV Date: Sun, 24 Jun 2007 17:58:46 -0700 Message-Id: <1182733127.6819.13.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.10.2 (2.10.2-2.fc7) Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1298 Lines: 32 > I wouldn't care if CONFIG_CC_OPTIMIZE_FOR_SIZE was hidden behind > CONFIG_EMBEDDED, but as long as it's available as a general purpose > option we have to consider it's performance. I think you are missing the point. You tell the kernel to OPTIMIZE_FOR_SIZE. *over performance*. Sure. Performance shouldn't be EXTREMELY pathetic, but it's not; and if it were, it's a problem with the gcc version you have (and if you are a distro, you can surely fix that) > > The interesting questions are: > Does -Os still sometimes generate faster code with gcc 4.2? > If yes, why? on a system level, size can help performance because you have more memory available for other things. It also reduces download size and gives you more space on the live CD.... if you want to make things bigger again, please do this OUTSIDE the "optimize for size" option. Because that TELLS you to go for size. -- if you want to mail me at work (you don't), use arjan (at) linux.intel.com Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.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/