Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752466AbbLUV42 (ORCPT ); Mon, 21 Dec 2015 16:56:28 -0500 Received: from mail-yk0-f174.google.com ([209.85.160.174]:36003 "EHLO mail-yk0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752425AbbLUV4Z (ORCPT ); Mon, 21 Dec 2015 16:56:25 -0500 MIME-Version: 1.0 In-Reply-To: <5677B3EB.9030908@jonmasters.org> References: <1A7043D5F58CCB44A599DFD55ED4C948469538F6@fmsmsx115.amr.corp.intel.com> <5677B3EB.9030908@jonmasters.org> Date: Mon, 21 Dec 2015 13:56:24 -0800 Message-ID: Subject: Re: Skylake (XPS 13 9350) TSC is way off From: John Stultz To: Jon Masters Cc: Andy Lutomirski , "Brown, Len" , "linux-kernel@vger.kernel.org" , X86 ML , "Hunter, Adrian" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1280 Lines: 33 On Mon, Dec 21, 2015 at 12:10 AM, Jon Masters wrote: > On 12/2/15, 6:55 PM, John Stultz wrote: >> >> On Wed, Dec 2, 2015 at 3:42 PM, Andy Lutomirski wrote: > > >>>> On a hunch, are you running chrony instead of ntpd? >>> >>> >>> Yes, this is indeed chrony. >> >> >> Ok. I'll have to look closer. The last time that message came up it >> was in a report of a bug that chrony uncovered with the internal >> correction being too slow. I know chrony is much more aggressive >> compared to ntpd in tweaking the freq value for the initial converging >> correction at startup, so maybe that along with something else is >> causing us to get out of spec. > > > Can you copy me on followup? I'm seeing similar behavior with chrony on > recent kernels on a couple of different ARM server prototype systems. A patch for this just landed in tip/timers/core and is pending for 4.5 http://git.kernel.org/cgit/linux/kernel/git/tip/tip.git/commit/?id=ec02b076ceab63f99e5b3d80fd223d777266c236 thanks -john -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/