From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 6558 invoked by alias); 10 Oct 2009 09:16:42 -0000 Received: (qmail 6550 invoked by uid 22791); 10 Oct 2009 09:16:42 -0000 X-SWARE-Spam-Status: No, hits=-2.5 required=5.0 tests=AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from moene.org (HELO moene.org) (82.95.66.103) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sat, 10 Oct 2009 09:16:37 +0000 Received: from [127.0.0.1] (ident=toon) by moene.org with esmtp (Exim 4.69) (envelope-from ) id 1MwY43-0001JJ-Gx for gcc@gcc.gnu.org; Sat, 10 Oct 2009 11:16:35 +0200 Message-ID: <4AD050F3.4030402@moene.org> Date: Sat, 10 Oct 2009 09:28:00 -0000 From: Toon Moene User-Agent: Mozilla-Thunderbird 2.0.0.22 (X11/20090707) MIME-Version: 1.0 To: gcc mailing list Subject: Re: LTO: Speedup. References: <4ACBA42B.8040107@moene.org> In-Reply-To: <4ACBA42B.8040107@moene.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org X-SW-Source: 2009-10/txt/msg00198.txt.bz2 I wrote: > On our weather forecasting code (compiled with -O3 -flto and linked with > -O3 -flto -fwhole-program) I get a speedup of 65 seconds per time step > in the model integration vs. 75 seconds with -O3 alone. > > That is a 10/75 ~ 13 % improvement. This morning I tried again, with a freshly updated trunk (so the correct behavior of -fwhole-program), and I got an additional 3 seconds (from 65 to 62 seconds per time step), which is ~ 5 %. -- Toon Moene - e-mail: toon@moene.org - phone: +31 346 214290 Saturnushof 14, 3738 XG Maartensdijk, The Netherlands At home: http://moene.org/~toon/ Progress of GNU Fortran: http://gcc.gnu.org/gcc-4.5/changes.html