From owner-freebsd-chat@FreeBSD.ORG Thu Oct 30 08:19:55 2003 Return-Path: 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 0A48D16A4CF for ; Thu, 30 Oct 2003 08:19:55 -0800 (PST) Received: from shiva.jussieu.fr (shiva.jussieu.fr [134.157.0.129]) by mx1.FreeBSD.org (Postfix) with ESMTP id 4802D43FDF for ; Thu, 30 Oct 2003 08:19:53 -0800 (PST) (envelope-from talon@lpthe.jussieu.fr) Received: from parthe.lpthe.jussieu.fr (parthe.lpthe.jussieu.fr [134.157.10.1])h9UGJp4B086404 for ; Thu, 30 Oct 2003 17:19:51 +0100 (CET) Received: from niobe (postfix@niobe.lpthe.jussieu.fr [134.157.10.41]) h9UGJkn12610 for ; Thu, 30 Oct 2003 17:19:46 +0100 Received: by niobe (Postfix, from userid 2005) id DD4B62D468; Thu, 30 Oct 2003 17:19:45 +0100 (CET) Date: Thu, 30 Oct 2003 17:19:45 +0100 From: Michel TALON To: chat@freebsd.org Message-ID: <20031030161945.GA18001@lpthe.jussieu.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.3.28i X-Antivirus: scanned by sophie at shiva.jussieu.fr Subject: Re: How much better are 64 but platforms X-BeenThere: freebsd-chat@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Non technical items related to the community List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 30 Oct 2003 16:19:55 -0000 On Wed, 29 Oct 2003, Bill Moran wrote: ... In the special case of the AMD64, which can run in 32 bits mode and 64 bits mode, choosing 64 bits mode not only means larger registers, possibly more traffic on the memory bus, potentially detrimental to performance, but also more registers, etc. This has the potential to give improved perfs, and indeed people speak of improvements of the order of 10 to 20% for "ordinary" programs, much more of course if you have enormous data sets requiring more than 4 gigs of memory to avoid swap. -- Michel TALON