From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 18471 invoked by alias); 14 Nov 2011 13:09:08 -0000 Received: (qmail 18426 invoked by uid 22791); 14 Nov 2011 13:09:07 -0000 X-SWARE-Spam-Status: No, hits=-2.9 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from localhost (HELO gcc.gnu.org) (127.0.0.1) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 14 Nov 2011 13:08:52 +0000 From: "burnus at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug libfortran/51119] MATMUL slow for large matrices Date: Mon, 14 Nov 2011 13:56:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: libfortran X-Bugzilla-Keywords: X-Bugzilla-Severity: enhancement X-Bugzilla-Who: burnus at gcc dot gnu.org X-Bugzilla-Status: ASSIGNED X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: jb at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: CC Message-ID: In-Reply-To: References: X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2011-11/txt/msg01382.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51119 Tobias Burnus changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |burnus at gcc dot gnu.org --- Comment #2 from Tobias Burnus 2011-11-14 13:08:49 UTC --- (In reply to comment #0) > Compared to ATLAS BLAS on an AMD 10h processor, MATMUL on square matrices with > n > 256 is around a factor of 8 slower. Side note: You can use -fexternal-blas -fblas-matmul-limit=<...> and link ATLAS BLAS. > Assigning to myself. > I have a cunning plan. I am looking forward to cunning ideas - at least if they are not too convoluted, work on all targets and are middle-end friendly.