From owner-freebsd-current@FreeBSD.ORG Sat May 26 10:48:40 2007 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id E258C16A41F for ; Sat, 26 May 2007 10:48:40 +0000 (UTC) (envelope-from shoesoft@gmx.net) Received: from mail.gmx.net (mail.gmx.net [213.165.64.20]) by mx1.freebsd.org (Postfix) with SMTP id 544F313C457 for ; Sat, 26 May 2007 10:48:40 +0000 (UTC) (envelope-from shoesoft@gmx.net) Received: (qmail invoked by alias); 26 May 2007 10:48:38 -0000 Received: from h081217094222.dyn.cm.kabsi.at (EHLO taxman.pepperland) [81.217.94.222] by mail.gmx.net (mp005) with SMTP; 26 May 2007 12:48:38 +0200 X-Authenticated: #16703784 X-Provags-ID: V01U2FsdGVkX1/Y3MJinT7YIJmfOiluIKt67IQud8FUEnelvuN3zF XwB04nghZ88DnA From: Stefan Ehmann To: freebsd-current@freebsd.org Date: Sat, 26 May 2007 12:48:36 +0200 User-Agent: KMail/1.9.6 References: <20070525095146.GA45288@freebsd.org> <200705251602.48778.shoesoft@gmx.net> <20070525150517.GA63514@freebsd.org> In-Reply-To: <20070525150517.GA63514@freebsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200705261248.37152.shoesoft@gmx.net> X-Y-GMX-Trusted: 0 Cc: Roman Divacky Subject: Re: size of kernel after gcc4.2 upgrade X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 26 May 2007 10:48:41 -0000 On Friday 25 May 2007 17:05:17 Roman Divacky wrote: > On Fri, May 25, 2007 at 04:02:47PM +0200, Stefan Ehmann wrote: > > On Friday 25 May 2007 11:51:46 Roman Divacky wrote: > > > hi > > > > > > I just noticed that > > > spravci ~# ls -l /boot/kernel*/kernel > > > -r-xr-xr-x 1 root wheel 3389971 May 18 12:03 > > > /boot/kernel.old/kernel* -r-xr-xr-x 1 root wheel 5211345 May 25 > > > 11:47 /boot/kernel/kernel* > > > > > > ie. after gcc42 import the kernel size increased roughly by 60% thats > > > a little too much. is there any forgotten option or something that > > > makes the kernel grow so big? > > > > While I also see an increase, it's not that much. > > > > GENERIC from today's current, also compiled with gcc34 from ports (I had > > to delete two gcc options in sys/conf/kern.mk): > > > > gcc34: 6530916 > > gcc42: 7352560 > > gcc34 -Os: 6074468 > > gcc42 -Os: 10058032 > > yes, thats it! I also used -Os. it looks like this occurs only with -Os > optimization level. > > can someone else confirm this? and/or possibly explain this? -Os seems to do more inlining than -O. Maybe this is a gcc bug, we use strange options for the buildkernel or who knows what. If I use INLINE_LIMIT=600, I get a more reasonable sized kernel (600 is the gcc default, /sys/conf/kern.mk sets it to 8000). But it's still larger than the -O compile. If I further lower INLINE_LIMIT to 50: -Os: 5876816 -O: 7154096 This numbers finally look sane for a -Os build. Doing this is probably not a good idea but maybe this points to the cause of the size increase.