From owner-freebsd-stable@freebsd.org Tue Jan 2 16:45:29 2018 Return-Path: Delivered-To: freebsd-stable@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id A1975EAE5B6 for ; Tue, 2 Jan 2018 16:45:29 +0000 (UTC) (envelope-from gpalmer@freebsd.org) Received: from mail.in-addr.com (mail.in-addr.com [IPv6:2a01:4f8:191:61e8::2525:2525]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 6BBEB6887E for ; Tue, 2 Jan 2018 16:45:29 +0000 (UTC) (envelope-from gpalmer@freebsd.org) Received: from gjp by mail.in-addr.com with local (Exim 4.90 (FreeBSD)) (envelope-from ) id 1eWPgs-000Hgz-Gy; Tue, 02 Jan 2018 16:45:26 +0000 Date: Tue, 2 Jan 2018 16:45:26 +0000 From: Gary Palmer To: Konstantin Belousov Cc: freebsd-stable@freebsd.org Subject: Re: Odd behaviour on recent boot of 11.1 with timecounters Message-ID: <20180102164526.GA63396@in-addr.com> References: <20171231141708.GA2629@in-addr.com> <20171231145147.GW1684@kib.kiev.ua> <20171231154913.GA63310@in-addr.com> <20171231164738.GY1684@kib.kiev.ua> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171231164738.GY1684@kib.kiev.ua> X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: gpalmer@freebsd.org X-SA-Exim-Scanned: No (on mail.in-addr.com); SAEximRunCond expanded to false X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 02 Jan 2018 16:45:29 -0000 On Sun, Dec 31, 2017 at 06:47:38PM +0200, Konstantin Belousov wrote: > On Sun, Dec 31, 2017 at 03:49:13PM +0000, Gary Palmer wrote: > > On Sun, Dec 31, 2017 at 04:51:47PM +0200, Konstantin Belousov wrote: > > > On Sun, Dec 31, 2017 at 02:17:08PM +0000, Gary Palmer wrote: > > > > > > > > Hi, > > > > > > > > I recently updated to 11.1-RELEASE-p6 and on the most recent reboot > > > > (after rebuilding all the necessary packages) the clock was running > > > > slow and NTP wouldn't sync. I looked in /var/log/messages and I found > > > > that for some reason, on this latest boot, it got the frequency of > > > > TSC-low wrong. > > > > > > > > Aug 24 04:55:35 my kernel: Timecounter "TSC-low" frequency 1746073190 Hz quality 1000 > > > > Aug 26 03:11:38 my kernel: Timecounter "TSC-low" frequency 1746070760 Hz quality 1000 > > > > Aug 26 14:12:46 my kernel: Timecounter "TSC-low" frequency 1746075204 Hz quality 1000 > > > > Nov 19 16:01:09 my kernel: Timecounter "TSC-low" frequency 1746070746 Hz quality 1000 > > > > Dec 27 22:28:00 my kernel: Timecounter "TSC-low" frequency 1746074808 Hz quality 1000 > > > > Dec 27 22:51:12 my kernel: Timecounter "TSC-low" frequency 1746071892 Hz quality 1000 > > > > Dec 28 12:50:46 my kernel: Timecounter "TSC-low" frequency 1746069704 Hz quality 1000 > > > > Dec 28 14:03:52 my kernel: Timecounter "TSC-low" frequency 1937876448 Hz quality 1000 > > > > > > > > Until the December reboots the machine was running 10.x. Dec 27 and later > > > > are part of the process to get up to 11.x. > > > > > > > > Any idea why the TSC-low frequency jumped 191,806,744Hz on the last > > > > measurement? > > > > > > > > I switched to HPET temporarily via sysctl and ntp seems happy. I'm just > > > > concerned that the problem might recur on later reboots as TSC-low seems > > > > to be the preferred timecounter. > > > > > > Show first 100 lines of the dmesg from a verbose boot. > > > Also check BIOS settings related to overclocking and powersaving. > > > > > > > Hi Konstantin, > > > > BIOS settings haven't been changed in 4+ years. No overclocking, and > > all powersaving options are at "auto" or "disabled". > > > > The first 100 lines of verbose dmesg didn't seem that interesting so > > I've included up to the end of "Device configuration finished" > > > > Note that this boot didn't have the TSC-low problem, and the boot > > that had it wasn't verbose unfortunately. > > It is really the CPU identification which I wanted to see. You have > IvyBridge, which is known to have good TSC. Ah > Try to obtain verbose dmesg with mis-identified frequency. Tried, and failed after 20+ reboots. I've left boot_verbose=" -v" in /boot/loader.conf to catch any boot-time wonkiness and undone it at runtime with debug.bootverbose=0 in /etc/sysctl.conf as I found that the snd_hda driver is ... chatty at runtime. Thanks, Gary