From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750881AbWGMNkK (ORCPT ); Thu, 13 Jul 2006 09:40:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751059AbWGMNkK (ORCPT ); Thu, 13 Jul 2006 09:40:10 -0400 Received: from mx1.redhat.com ([66.187.233.31]:16836 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S1750881AbWGMNkI (ORCPT ); Thu, 13 Jul 2006 09:40:08 -0400 Message-ID: <44B64CAD.5080804@redhat.com> Date: Thu, 13 Jul 2006 09:37:49 -0400 From: Bhavana Nagendra User-Agent: Mozilla Thunderbird 1.0.7-1.4.1 (X11/20050929) X-Accept-Language: en-us, en MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: RE: [discuss] Re: [PATCH] Allow all Opteron processors to change pstate at same time Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Here are some results without changing frequencies on a system whose BIOS does not support Power Now! on MP systems: Basically the system booted up with "nohpet, nopmtimer"i.e. using TSC as the GTOD time source and system stayed idle for 13 hours. There appears to be drift of 20 secs in the CPU 2 readings. This TSC drift will be worse when the system is active and doing GTOD operations. CPU 2: Syncing TSC to CPU 0. CPU 2: synchronized TSC with CPU 0 (last diff -108 cycles, maxerr 826 cycles) CPU 3: Syncing TSC to CPU 0. CPU 3: synchronized TSC with CPU 0 (last diff -119 cycles, maxerr 845 cycles) *** CPUs go offline *** *** back online *** CPU 2: Syncing TSC to CPU 0. CPU 2: synchronized TSC with CPU 0 (last diff -117 cycles, maxerr 846 cycles) CPU 3: Syncing TSC to CPU 0. CPU 3: synchronized TSC with CPU 0 (last diff -117 cycles, maxerr 845 cycles)