From owner-freebsd-amd64@FreeBSD.ORG Wed Feb 25 10:28:18 2004 Return-Path: Delivered-To: freebsd-amd64@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 8BB3316A4CE for ; Wed, 25 Feb 2004 10:28:18 -0800 (PST) Received: from dragon.nuxi.com (trang.nuxi.com [66.93.134.19]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2594543D2D for ; Wed, 25 Feb 2004 10:28:18 -0800 (PST) (envelope-from obrien@NUXI.com) Received: from dragon.nuxi.com (obrien@localhost [127.0.0.1]) by dragon.nuxi.com (8.12.10/8.12.10) with ESMTP id i1PISEOJ026228; Wed, 25 Feb 2004 10:28:14 -0800 (PST) (envelope-from obrien@dragon.nuxi.com) Received: (from obrien@localhost) by dragon.nuxi.com (8.12.11/8.12.11/Submit) id i1PISDCw026227; Wed, 25 Feb 2004 10:28:13 -0800 (PST) (envelope-from obrien) Date: Wed, 25 Feb 2004 10:28:13 -0800 From: "David O'Brien" To: Brooks Davis Message-ID: <20040225182813.GE7567@dragon.nuxi.com> References: <1077658664.92943.15.camel@.rochester.rr.com> <20040224215847.GC6356@Odin.AC.HMC.Edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040224215847.GC6356@Odin.AC.HMC.Edu> User-Agent: Mutt/1.4.1i X-Operating-System: FreeBSD 5.2-CURRENT Organization: The NUXI BSD Group X-Pgp-Rsa-Fingerprint: B7 4D 3E E9 11 39 5F A3 90 76 5D 69 58 D9 98 7A X-Pgp-Rsa-Keyid: 1024/34F9F9D5 cc: Jem Matzan cc: "'freebsd-amd64@FreeBSD.org'" Subject: Re: Performance comparison, ULE vs 4BSD and AMD64 vs i386 X-BeenThere: freebsd-amd64@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list Reply-To: freebsd-amd64@freebsd.org List-Id: Porting FreeBSD to the AMD64 platform List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 25 Feb 2004 18:28:18 -0000 On Tue, Feb 24, 2004 at 01:58:47PM -0800, Brooks Davis wrote: > > How about AMD64 being slower than i386 on the same hardware? By > > slower, I mean a buildworld -j4 took about 400 seconds longer in AMD64 > > mode. > > You can't usefully compare compile times when you are compiling for > a different instructions set. The work involved is rairly the same > so the results are meaning less. If you could factor out the cost of > building the native bootstrap tools since that isn't the same job on > each machine, the speed of a cross buildworld would be an intresting > test. For comparing i386 and amd64, I'd probably build an alpha or > sparc64 world so the target would be entierly different. While generally true (everyone used to compare i386 & Alpha); the 80% of the amd64 instruction set is the i386 instruction set, and most of the code generation code is shared between the two. -- -- David (obrien@FreeBSD.org)