From owner-freebsd-questions@FreeBSD.ORG Fri Dec 26 14:48:07 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4EE4A106579B for ; Fri, 26 Dec 2008 14:48:02 +0000 (UTC) (envelope-from talon@lpthe.jussieu.fr) Received: from shiva.jussieu.fr (shiva.jussieu.fr [134.157.0.129]) by mx1.freebsd.org (Postfix) with ESMTP id 3324C8FC17 for ; Fri, 26 Dec 2008 14:48:02 +0000 (UTC) (envelope-from talon@lpthe.jussieu.fr) Received: from parthe.lpthe.jussieu.fr (parthe.lpthe.jussieu.fr [134.157.10.1]) by shiva.jussieu.fr (8.14.3/jtpda-5.4) with ESMTP id mBQEm0CR060989 for ; Fri, 26 Dec 2008 15:48:00 +0100 (CET) X-Ids: 166 Received: from niobe.lpthe.jussieu.fr (niobe.lpthe.jussieu.fr [134.157.10.41]) by parthe.lpthe.jussieu.fr (Postfix) with ESMTP id 2FA1D8A265 for ; Fri, 26 Dec 2008 15:47:59 +0100 (CET) Received: by niobe.lpthe.jussieu.fr (Postfix, from userid 2005) id 1F2D115; Fri, 26 Dec 2008 15:47:59 +0100 (CET) Date: Fri, 26 Dec 2008 15:47:59 +0100 From: Michel Talon To: freebsd-questions@freebsd.org Message-ID: <20081226144759.GA3715@lpthe.jussieu.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.2.3i X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0.1 (shiva.jussieu.fr [134.157.0.166]); Fri, 26 Dec 2008 15:48:00 +0100 (CET) X-Virus-Scanned: ClamAV 0.94.2/8801/Fri Dec 26 02:02:43 2008 on shiva.jussieu.fr X-Virus-Status: Clean X-Miltered: at jchkmail.jussieu.fr with ID 4954EEA0.003 by Joe's j-chkmail (http : // j-chkmail dot ensmp dot fr)! X-j-chkmail-Enveloppe: 4954EEA0.003/134.157.10.1/parthe.lpthe.jussieu.fr/parthe.lpthe.jussieu.fr/ X-j-chkmail-Score: MSGID : 4954EEA0.003 on jchkmail.jussieu.fr : j-chkmail score : . : R=. U=. O=. B=0.014 -> S=0.014 X-j-chkmail-Status: Ham Subject: Re: Dell 2850 use 32 or 64 bit? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 26 Dec 2008 14:48:07 -0000 Tim Kellers wrote: > Thanks for the reply. I already know it is 64 bit capable. I 'm > interested in finding out if their are measurable performance advantages > to running it using 64 v 32 bit FreeBSD. For the type of use of the OP (databases, etc.) i don't know, but for scientific computations we observe a massive performance advantage running in 64 bits mode (by this i mean more than 20%, i have seen some Maple formal computations run 100% faster). The only problem with 64 bits mode is that some ports may have problems, but, as far as i know, these ports are more desktop oriented than server oriented. For a server i don't see a reason to run in 32 bits mode. Contrary to some frequent assertions the increase in size of binaries is extremely limited as can easily be checked. This is very largely compensated by the increase in the number of registers. The possibility of using more than 4 gigs memory is just one advantage of 64 bits mode, and by the way, very few of our machines have more than 4 gigs memory, and they don't lack it at all. -- Michel TALON