From owner-freebsd-current@FreeBSD.ORG Tue Jun 5 13:16:45 2007 Return-Path: X-Original-To: freebsd-current@FreeBSD.ORG Delivered-To: freebsd-current@FreeBSD.ORG Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 003EF16A469 for ; Tue, 5 Jun 2007 13:16:44 +0000 (UTC) (envelope-from olli@lurza.secnetix.de) Received: from lurza.secnetix.de (lurza.secnetix.de [83.120.8.8]) by mx1.freebsd.org (Postfix) with ESMTP id 6EC9E13C458 for ; Tue, 5 Jun 2007 13:16:44 +0000 (UTC) (envelope-from olli@lurza.secnetix.de) Received: from lurza.secnetix.de (wtcfqp@localhost [127.0.0.1]) by lurza.secnetix.de (8.13.4/8.13.4) with ESMTP id l55DGSC7052273; Tue, 5 Jun 2007 15:16:34 +0200 (CEST) (envelope-from oliver.fromme@secnetix.de) Received: (from olli@localhost) by lurza.secnetix.de (8.13.4/8.13.1/Submit) id l55DGSU0052272; Tue, 5 Jun 2007 15:16:28 +0200 (CEST) (envelope-from olli) Date: Tue, 5 Jun 2007 15:16:28 +0200 (CEST) Message-Id: <200706051316.l55DGSU0052272@lurza.secnetix.de> From: Oliver Fromme To: freebsd-current@FreeBSD.ORG, almarrie@gmail.com, jroberson@chesapeake.net In-Reply-To: <499c70c0706050348x3cf9e50fn929b910e7c6b0519@mail.gmail.com> X-Newsgroups: list.freebsd-current User-Agent: tin/1.8.2-20060425 ("Shillay") (UNIX) (FreeBSD/4.11-STABLE (i386)) MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-2.1.2 (lurza.secnetix.de [127.0.0.1]); Tue, 05 Jun 2007 15:16:34 +0200 (CEST) Cc: Subject: Re: Intel C2D COREs not used equally in FreeBSD 7.0-CURRENT i386 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: freebsd-current@FreeBSD.ORG, almarrie@gmail.com, jroberson@chesapeake.net List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 05 Jun 2007 13:16:45 -0000 Abdullah Ibn Hamad Al-Marri wrote: > Jeff Roberson wrote: > > CORE is no longer supported and has been removed from the tree. If you > > would like to try something new you can cvsup to sources from tonight and > > apply this patch: > > > > http://people.freebsd.org/~jeff/schedsmp.diff > > > > Then use options SCHED_SMP, which is a ULE variant. Please report back > > your findings if you do try this. However, it only works on amd64. > > I can't wait for it if it's for i386. ;) > > Would you implement it for i386 in the future too, or it's exclusive > for AMD64? :) > > I don't have 4 GB ram, and I don't see a strong reason to switch to > AMD64 with 2 GB of ram, It's a common mistake to assume that amd64 only makes sense if you have >= 4GB RAM. There are several reasons why it might be useful to switch from i386 to amd64: - Most programs (though not all) will run faster, because in amd64 mode there are twice as many general-purpose registers, giving compilers much better opportunities for optimizations and caching of values, and reducing slow memory accesses. - Programs that use a lot of "long" values (64bit) will run faster because the processor can handle them natively. In i386 mode those values have to be split into two 32bit parts, reducing performance noticeably. - Some applications might benefit from a larger virtual address space > 4 GB. (Note that this is not related to the amount of physical RAM!) > beside 95% of the ports are 32bits even they > can run in AMD64. I'm not sure I understand that sentence correctly, but every possible interpretation is complete nonsense. First, ports are neither 32bit nor 64bit, except for binary ports, but that's a small minority. Once you build a port, it becomes either a 32bit binary or a 64bit binary, depending on the architecture on which you build it. Second, my guess is that > 95% of the ports are 64bit- clean and will run on amd64 as native 64bit binaries. In practice there's (almost) only one reason not to run FreeBSD/amd64 on amd64-capable hardware: If you depend on a certain piece of software which is known not to run correctly in 64bit mode. Fortunately those are not many. Best regards Oliver -- Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing b. M. Handelsregister: Registergericht Muenchen, HRA 74606, Geschäftsfuehrung: secnetix Verwaltungsgesellsch. mbH, Handelsregister: Registergericht Mün- chen, HRB 125758, Geschäftsführer: Maik Bachmann, Olaf Erb, Ralf Gebhart FreeBSD-Dienstleistungen, -Produkte und mehr: http://www.secnetix.de/bsd 'Instead of asking why a piece of software is using "1970s technology," start asking why software is ignoring 30 years of accumulated wisdom.'