From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754034AbZEKGyd (ORCPT ); Mon, 11 May 2009 02:54:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751600AbZEKGyZ (ORCPT ); Mon, 11 May 2009 02:54:25 -0400 Received: from science.horizon.com ([192.35.100.1]:45043 "HELO science.horizon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751417AbZEKGyY (ORCPT ); Mon, 11 May 2009 02:54:24 -0400 Date: 11 May 2009 02:54:24 -0400 Message-ID: <20090511065424.25138.qmail@science.horizon.com> From: "George Spelvin" To: johnstul@us.ibm.com, linux@horizon.com Subject: Re: [RFC][PATCH] tsc_khz= boot option to avoid TSC calibration variance Cc: linux-kernel@vger.kernel.org, mingo@elte.hu, tglx@linutronix.de, ulrich.windl@rz.uni-regensburg.de, williams@redhat.com, zippel@linux-m68k.org In-Reply-To: <1241809372.7297.3.camel@localhost.localdomain> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Just as a data point, I have this patch running on two PPS-synced NTP servers with apparent success. After thinking through the sign conventions carefully, (if NTP reports a that it is applying a positive clock frequency adjustment, the TSC frequency should be reduced by that amount), I now have the NTP frequency offset within a couple PPM of 0. Thanks for the patch!