From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Thu, 05 Jun 2003 00:46:55 +0100 (BST) Received: from gateway-1237.mvista.com ([IPv6:::ffff:12.44.186.158]:47094 "EHLO orion.mvista.com") by linux-mips.org with ESMTP id ; Thu, 5 Jun 2003 00:46:53 +0100 Received: (from jsun@localhost) by orion.mvista.com (8.11.6/8.11.6) id h54Nkqm24427; Wed, 4 Jun 2003 16:46:52 -0700 Date: Wed, 4 Jun 2003 16:46:52 -0700 From: Jun Sun To: Ralf Baechle Cc: linux-mips@linux-mips.org, jsun@mvista.com Subject: Re: [RFC] synchronized CPU count registers on SMP machines Message-ID: <20030604164652.J19122@mvista.com> References: <20030604153930.H19122@mvista.com> <20030604231547.GA22410@linux-mips.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20030604231547.GA22410@linux-mips.org>; from ralf@linux-mips.org on Thu, Jun 05, 2003 at 01:15:47AM +0200 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: 2527 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: jsun@mvista.com Precedence: bulk X-list: linux-mips On Thu, Jun 05, 2003 at 01:15:47AM +0200, Ralf Baechle wrote: > On Wed, Jun 04, 2003 at 03:39:30PM -0700, Jun Sun wrote: > > > 1) clocks on different CPUs don't have the same frequency > > 2) clocks on different CPUs drift to each other > > 2) some fancy power saving feature such as frequency scaling > > > > But I think for a foreseeable future most MIPS SMP machines > > don't have the above issues (true?). And it is probably worthwile > > to synchronize count registers for them. > > 1) and 2) affect most SGI systems. > Assuming SGI systems represent the past of MIPS, we are still ok future-wise. :) Jun