From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Thu, 05 Jun 2003 01:12:36 +0100 (BST) Received: from p508B7EE4.dip.t-dialin.net ([IPv6:::ffff:80.139.126.228]:50654 "EHLO dea.linux-mips.net") by linux-mips.org with ESMTP id ; Thu, 5 Jun 2003 01:12:34 +0100 Received: from dea.linux-mips.net (localhost [127.0.0.1]) by dea.linux-mips.net (8.12.8/8.12.8) with ESMTP id h550CXbY006014; Wed, 4 Jun 2003 17:12:33 -0700 Received: (from ralf@localhost) by dea.linux-mips.net (8.12.8/8.12.8/Submit) id h550CW2O006013; Thu, 5 Jun 2003 02:12:33 +0200 Date: Thu, 5 Jun 2003 02:12:32 +0200 From: Ralf Baechle To: Jun Sun Cc: linux-mips@linux-mips.org Subject: Re: [RFC] synchronized CPU count registers on SMP machines Message-ID: <20030605001232.GA5626@linux-mips.org> References: <20030604153930.H19122@mvista.com> <20030604231547.GA22410@linux-mips.org> <20030604164652.J19122@mvista.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030604164652.J19122@mvista.com> User-Agent: Mutt/1.4.1i Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 2528 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: ralf@linux-mips.org Precedence: bulk X-list: linux-mips On Wed, Jun 04, 2003 at 04:46:52PM -0700, Jun Sun wrote: > Assuming SGI systems represent the past of MIPS, we are still ok > future-wise. :) You loose. The reasons why SGI did construct their systems that way are still valid. It can be quite tricky to distribute the clock in large systems - even for a moderate definition of large. And for ccNUMAs which are going to show up on the embedded market sooner or later it's easy for the lazy designer to use several clock sources anyway. Note our current time code for will not work properly if clocks diverge on the slightest bit - among other things the standards mandate time to monotonically increase. Ralf