From owner-freebsd-hackers@FreeBSD.ORG Mon Jun 18 21:49:07 2007 Return-Path: X-Original-To: freebsd-hackers@freebsd.org Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 66B5616A46C for ; Mon, 18 Jun 2007 21:49:07 +0000 (UTC) (envelope-from almarrie@gmail.com) Received: from an-out-0708.google.com (an-out-0708.google.com [209.85.132.247]) by mx1.freebsd.org (Postfix) with ESMTP id 23FE713C45E for ; Mon, 18 Jun 2007 21:49:06 +0000 (UTC) (envelope-from almarrie@gmail.com) Received: by an-out-0708.google.com with SMTP id c14so421609anc for ; Mon, 18 Jun 2007 14:49:06 -0700 (PDT) DKIM-Signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=OTXP1kMDDJXvJwemgOZ0NfnofiyIqaPPPRDf94nK/+ChnuoN+EeWGhjtDqSFMe2rVDangrjk9r7fOTRjhZem4GeMzyXlIdoawJH4SiE26ljN6wN62D9DBD5FMREeZZ5NFHQPFdA7uIbVb2ktwWn4ZIihUdCh9x+q9dSEVsH9eUM= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=Dt9ksqt0NEyTo9xuGMgBdbAZGdZVUH0zwvTqubWB3nE2Gjxf2uz7vCbICva7381TNRY0BVagCTISnaxk67A9p+VODuV4+F4UBPuWIEN+rW0JvMGEs+mZLm6V/jBfIR+ihV5ebvA8dI4sC5gDrbR43GDgPiqy87bg8L/5GrKyE+M= Received: by 10.100.135.16 with SMTP id i16mr3826996and.1182203346426; Mon, 18 Jun 2007 14:49:06 -0700 (PDT) Received: by 10.100.9.14 with HTTP; Mon, 18 Jun 2007 14:49:06 -0700 (PDT) Message-ID: <499c70c0706181449o7abf6b24uc657c2b312add822@mail.gmail.com> Date: Tue, 19 Jun 2007 00:49:06 +0300 From: "Abdullah Ibn Hamad Al-Marri" To: "Martin Turgeon" In-Reply-To: <322073cc0706181415o17ecd532i971d8bdf5ea1dafd@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <4676BAF0.4030703@gmail.com> <20070618180813.GA13003@eos.sc1.parodius.com> <322073cc0706181415o17ecd532i971d8bdf5ea1dafd@mail.gmail.com> Cc: freebsd-hackers@freebsd.org, Jeremy Chadwick Subject: Re: i386 with PAE or AMD64 on PowerEdge with 4G RAM X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 18 Jun 2007 21:49:07 -0000 On 6/19/07, Martin Turgeon wrote: > 2007/6/18, Jeremy Chadwick : > > > > On Mon, Jun 18, 2007 at 01:03:44PM -0400, Martin Turgeon wrote: > > > I just receive 2 PowerEdge servers (a 1950 and a 860) both with 4G of > > RAM. I > > > installed FreeBSD 6.2 Release i386 on both of them. Unfortunately, only > > 3,5G > > > is recognized on the 860 and 3,3G on the 1950. > > > dmesg on 860: > > > real memory = 3757834240 (3583 MB) > > > avail memory = 3678318592 (3507 MB) > > > > > > I am facing a difficult decision. Should I use i386 with PAE enabled in > > the > > > kernel (I read a lot of warnings using it) or should I go with AMD64? > > Which > > > branch should I follow? > > > > Based on what I've read from some of the porters and miscellaneous > > others, generally-speaking there's too many issues with amd64 (in the > > sense of 32-bit vs. 64-bit compatibility -- not the fault of the kernel > > or otherwise) to consider it worth switching to. > > > > I personally don't run 64-bit OSes because most developers still use > > 32-bit machines and don't have a way to develop/test in 64-bit > > environments. > > > > That said, I'd recommend you stick with i386 + PAE, simply for > > guaranteed application compatibility. > > > My setup is fairly standard (as I described), should I expect problem with > 64 bit version of these programs? > > > You'll lose the amount of RAM you're seeing due to PAE addressing for > > PCI address space. I can dig you up a usage map (broken down by how > > much is taken up by each portion; PCI, ACPI, etc.) if you want one. > > It's for SuperMicro systems, but the general idea applies to most > > everything. > > > I'm not sure to understand what you mean by that. Are you saying that PAE > will eat the 500M that should be available? > > -- > > | Jeremy Chadwick jdc at parodius.com | > > | Parodius Networking http://www.parodius.com/ | > > | UNIX Systems Administrator Mountain View, CA, USA | > > | Making life hard for others since 1977. PGP: 4BD6C0CB | If I were you, I would go for AMD64. -- Regards, -Abdullah Ibn Hamad Al-Marri Arab Portal http://www.WeArab.Net/