From owner-freebsd-hackers@FreeBSD.ORG Sun Sep 12 20:01:32 2004 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2FA7316A4CE for ; Sun, 12 Sep 2004 20:01:32 +0000 (GMT) Received: from smtpout.mac.com (smtpout.mac.com [17.250.248.89]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1991243D46 for ; Sun, 12 Sep 2004 20:01:32 +0000 (GMT) (envelope-from leimy2k@mac.com) Received: from mac.com (smtpin01-en2 [10.13.10.146]) by smtpout.mac.com (Xserve/MantshX 2.0) with ESMTP id i8CK1V2G020608; Sun, 12 Sep 2004 13:01:31 -0700 (PDT) Received: from [192.168.1.100] (c-67-165-114-246.client.comcast.net [67.165.114.246]) (authenticated bits=0)i8CK1Vrx029816; Sun, 12 Sep 2004 13:01:31 -0700 (PDT) In-Reply-To: References: Mime-Version: 1.0 (Apple Message framework v619) Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Message-Id: <88A2EE14-04F6-11D9-8975-000A95AFBEB4@mac.com> Content-Transfer-Encoding: 7bit From: David Leimbach Date: Sun, 12 Sep 2004 13:01:28 -0700 To: Igor Shmukler X-Mailer: Apple Mail (2.619) X-Mailman-Approved-At: Mon, 13 Sep 2004 15:13:54 +0000 cc: freebsd-hackers@freebsd.org Subject: Re: Re[4]: FreeBSD on Xserve ? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 12 Sep 2004 20:01:32 -0000 On Sep 12, 2004, at 12:38 PM, Igor Shmukler wrote: >>> Why do you think that 970 does not have BAT registers? >>> There are 16 special purpose registers specifically to implement >>> Block >>> Address Translation. >>> >> >> Because Peter already told us that they have no BAT registers: >> >> http://lists.freebsd.org/pipermail/freebsd-ppc/2004-February/ >> 000359.html > > I don't know what Peter said, but I do have documentation in front of > me. > In 7.4 of Programming Environments Manual we have an overview of BAT > including BAT array organization. > > This comes as a shock to me. I am sending carbon copy to Peter Grehan, > perhaps he could tell us where he got his information. > > I am not trying to suggest that you and/or him are wrong, but I cannot > find (in manual) anything that would support your position that 970 > has no block address translation. Regarding 16MB superpages, I believe > manual explicitly says that 970 has no superpages, but I did not go > through the doc again. Therefore, I could be mistaken. > I understand :). I am not able to confirm this information with anything technical as I haven't looked very hard or had the time to check into these issues. > Regarding fans, it's not a big deal to support this kind of equipment. > IMO, SMP support and other low-level stuff is order[s] of magnitude > more complex. I agree. It's just the fans would likely be an issue for many users who have G5 desktops. An Xserve in a rack is probably allowed to be more noisy than other stuff. And I hope that you are correct about the BAT registers :). Dave > > Igor.