From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759838AbbIDQgR (ORCPT ); Fri, 4 Sep 2015 12:36:17 -0400 Received: from www.linutronix.de ([62.245.132.108]:54186 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759407AbbIDQgN (ORCPT ); Fri, 4 Sep 2015 12:36:13 -0400 Date: Fri, 4 Sep 2015 18:35:18 +0200 (CEST) From: Thomas Gleixner To: Peter Zijlstra cc: Richard Cochran , "Hall, Christopher S" , "Kirsher, Jeffrey T" , "hpa@zytor.com" , "mingo@redhat.com" , "john.stultz@linaro.org" , "x86@kernel.org" , "linux-kernel@vger.kernel.org" , "netdev@vger.kernel.org" , "intel-wired-lan@lists.osuosl.org" Subject: Re: [PATCH v3 1/4] Add correlated clocksource deriving system time from an auxiliary clocksource In-Reply-To: <20150904154133.GI18489@twins.programming.kicks-ass.net> Message-ID: References: <1440183128-1384-1-git-send-email-christopher.s.hall@intel.com> <1440183128-1384-2-git-send-email-christopher.s.hall@intel.com> <20150904151021.GF18489@twins.programming.kicks-ass.net> <20150904151743.GB16862@localhost.localdomain> <20150904154133.GI18489@twins.programming.kicks-ass.net> User-Agent: Alpine 2.11 (DEB 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 4 Sep 2015, Peter Zijlstra wrote: > On Fri, Sep 04, 2015 at 05:17:43PM +0200, Richard Cochran wrote: > > On Fri, Sep 04, 2015 at 05:10:21PM +0200, Peter Zijlstra wrote: > > > I think what they're getting at is asking if there's a rate limit to > > > time adjustments, without that, saving the last n transition points will > > > still not cover any given length of history. > > > > As if the ntp code isn't complex enough already - now we're adding > > sample histories and adjustment rating limiting? > > > > And all for some unknown DSP in a mythical sound card?? > > Hehe, I'm just a 'translator' here. But going by you answer I'm taking > it there isn't in fact a rate-limit to adjustments. Which, even if you > were not opposed to that direction, makes it an unfeasible proposition. > > Also, I'm not thinking its too mythical, sound/soc/intel/ is full of > audio DSP stuff, I think a newer version will just gain ART support. Right, but we still do not know how that is going to be used. And that's the key question. As long as that is not answered all can do is wild guessing. Thanks, tglx