From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752256Ab3LJL0J (ORCPT ); Tue, 10 Dec 2013 06:26:09 -0500 Received: from mx1.redhat.com ([209.132.183.28]:20816 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751406Ab3LJL0I (ORCPT ); Tue, 10 Dec 2013 06:26:08 -0500 Date: Tue, 10 Dec 2013 12:26:04 +0100 From: Miroslav Lichvar To: John Stultz Cc: linux-kernel@vger.kernel.org, Prarit Bhargava , Richard Cochran Subject: Re: [PATCH RFC] timekeeping: Fix clock stability with nohz Message-ID: <20131210112604.GQ22878@localhost> References: <1384440640-9482-1-git-send-email-mlichvar@redhat.com> <528A7C88.1030801@linaro.org> <20131120183900.GA25735@localhost> <529D2BA6.5020005@linaro.org> <529D5805.20903@linaro.org> <20131206142602.GH22878@localhost> <52A27D51.1040805@linaro.org> <20131210102051.GO22878@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131210102051.GO22878@localhost> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Dec 10, 2013 at 11:20:51AM +0100, Miroslav Lichvar wrote: > What does the following line from your patch mean? > > tick_error -= tk->xtime_interval; Ok, I think I understand how it should work. There are two loops, the bigadjust one is correcting only for ntp tick length and the other for the cumulative error. I think it might work better if they were both active at the same time instead of switching between them according to the current ntp error. -- Miroslav Lichvar