From owner-freebsd-chat Sun Jan 5 11:26:12 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 9CFCC37B401 for ; Sun, 5 Jan 2003 11:26:11 -0800 (PST) Received: from avocet.mail.pas.earthlink.net (avocet.mail.pas.earthlink.net [207.217.120.50]) by mx1.FreeBSD.org (Postfix) with ESMTP id A681343EE5 for ; Sun, 5 Jan 2003 11:26:10 -0800 (PST) (envelope-from rsidd@papagena.rockefeller.edu) Received: from user-0cev12d.cable.mindspring.com ([24.239.132.77] helo=bluerondo) by avocet.mail.pas.earthlink.net with esmtp (Exim 3.33 #1) id 18VGPR-0005qw-01 for chat@FreeBSD.org; Sun, 05 Jan 2003 11:26:09 -0800 Received: (qmail 6755 invoked by uid 1001); 5 Jan 2003 19:25:57 -0000 Date: Sun, 5 Jan 2003 14:25:56 -0500 From: Rahul Siddharthan To: Brett Glass Cc: Terry Lambert , Greg 'groggy' Lehey , chat@FreeBSD.org Subject: Re: Bystander shot by a spam filter Message-ID: <20030105192556.GA526@papagena.rockefeller.edu> References: <3E18073C.68182FE4@mindspring.com> <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> <20030105074923.GA4956@papagena.rockefeller.edu> <3E18073C.68182FE4@mindspring.com> <4.3.2.7.2.20030105120224.029377d0@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4.3.2.7.2.20030105120224.029377d0@localhost> 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 Brett Glass said on Jan 5, 2003 at 12:03:36: > At 06:34 AM 1/5/2003, Rahul Siddharthan wrote: > > >The point is, sparse matrix operations and LU decomposition are > >exactly the cases Brett is talking about. > > Our primary interest wasn't sparse matrix operations. You did say you were interested in heavily nested loops and floating point arithmetic. Sparse matrix operations qualify. It is interesting, in fact, that gcc does well in all such problems. It doesn't do very well in Gauss-Siedel relaxation (which is a fairly straightforward iterative method) and does quite badly in a monte-carlo integration (which is basically just one long loop with calls to a random number generator and the function evaluator). Again, gcc does well on the mazebench and Stepanov benchmarks, and badly on the rather meaningless Whetstone benchmark. Perhaps Intel produces better "straight" code than gcc -- not surprising if it's their chip -- but gcc actually does better optimization, and therefore catches up on more complex code? - Rahul To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-chat" in the body of the message