From owner-freebsd-chat Sat Jan 4 23:49:40 2003 Delivered-To: freebsd-chat@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id CF47B37B401 for ; Sat, 4 Jan 2003 23:49:39 -0800 (PST) Received: from swan.mail.pas.earthlink.net (swan.mail.pas.earthlink.net [207.217.120.123]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1014543E4A for ; Sat, 4 Jan 2003 23:49:39 -0800 (PST) (envelope-from rsidd@papagena.rockefeller.edu) Received: from user-0cev12d.cable.mindspring.com ([24.239.132.77] helo=dhcp-906-242) by swan.mail.pas.earthlink.net with esmtp (Exim 3.33 #1) id 18V5XK-0004oQ-00 for chat@FreeBSD.ORG; Sat, 04 Jan 2003 23:49:35 -0800 Received: (qmail 16188 invoked by uid 1001); 5 Jan 2003 07:49:23 -0000 Date: Sun, 5 Jan 2003 02:49:23 -0500 From: Rahul Siddharthan To: Greg 'groggy' Lehey Cc: Brett Glass , chat@FreeBSD.ORG Subject: Re: Bystander shot by a spam filter Message-ID: <20030105074923.GA4956@papagena.rockefeller.edu> References: <4.3.2.7.2.20030104201251.029387d0@localhost> <4.3.2.7.2.20030104112015.026a5530@localhost> <4.3.2.7.2.20030104201251.029387d0@localhost> <4.3.2.7.2.20030104202908.03c3b100@localhost> <20030105073804.GA72674@wantadilla.lemis.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030105073804.GA72674@wantadilla.lemis.com> User-Agent: Mutt/1.4i X-Operating-System: FreeBSD 5.0-CURRENT i386 Sender: owner-freebsd-chat@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org Greg 'groggy' Lehey said on Jan 5, 2003 at 18:08:04: > On Saturday, 4 January 2003 at 20:31:52 -0700, Brett Glass wrote: > > At 08:22 PM 1/4/2003, Rahul Siddharthan wrote: > > > >> So you disassembled and examined it? Or did you benchmark it? > > > > Actually, both. In heavy matrix math (with lots of determinants, > > inversions, etc.), Intel beats GCC by a mile. Ditto on "bit-banging" > > (bit manipulation, especially for graphics). Didn't disassemble the > > code, though; just asked the compilers to output assembler. The > > GCC output was so naive it made me wince. > > I'd be interested to see some examples. I'd be surprised to see them. As I said, my code involves plenty of nested loops, linear algebra and floating point operations and the performance is quite respectable. According to the benchmarks I cited earlier, http://www.coyotegulch.com/reviews/intel_comp/intel_gcc_bench2.html (look at the SciMark benchmark) gcc actually beats intel on the sparse matrix multiply on the Pentium IV (which generally emerges as Intel's strong platform) and runs it pretty close on LU decomposition. - Rahul To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-chat" in the body of the message