From owner-freebsd-stable@FreeBSD.ORG Thu Oct 11 06:30:37 2012 Return-Path: Delivered-To: freebsd-stable@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id AEB04EF1; Thu, 11 Oct 2012 06:30:37 +0000 (UTC) (envelope-from jmg@h2.funkthat.com) Received: from h2.funkthat.com (gate2.funkthat.com [208.87.223.18]) by mx1.freebsd.org (Postfix) with ESMTP id 53F188FC0C; Thu, 11 Oct 2012 06:30:37 +0000 (UTC) Received: from h2.funkthat.com (localhost [127.0.0.1]) by h2.funkthat.com (8.14.3/8.14.3) with ESMTP id q9B6UUru096214 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 10 Oct 2012 23:30:31 -0700 (PDT) (envelope-from jmg@h2.funkthat.com) Received: (from jmg@localhost) by h2.funkthat.com (8.14.3/8.14.3/Submit) id q9B6UUbT096213; Wed, 10 Oct 2012 23:30:30 -0700 (PDT) (envelope-from jmg) Date: Wed, 10 Oct 2012 23:30:30 -0700 From: John-Mark Gurney To: Alexander Motin Subject: Re: time keeps on slipping... slipping... Message-ID: <20121011063030.GK1967@funkthat.com> Mail-Followup-To: Alexander Motin , freebsd-stable@FreeBSD.org References: <20121008040239.GE1967@funkthat.com> <5075F9F7.1040007@FreeBSD.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5075F9F7.1040007@FreeBSD.org> User-Agent: Mutt/1.4.2.3i X-Operating-System: FreeBSD 7.2-RELEASE i386 X-PGP-Fingerprint: 54BA 873B 6515 3F10 9E88 9322 9CB1 8F74 6D3F A396 X-Files: The truth is out there X-URL: http://resnet.uoregon.edu/~gurney_j/ X-Resume: http://resnet.uoregon.edu/~gurney_j/resume.html X-to-the-FBI-CIA-and-NSA: HI! HOW YA DOIN? can i haz chizburger? X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.2 (h2.funkthat.com [127.0.0.1]); Wed, 10 Oct 2012 23:30:31 -0700 (PDT) Cc: freebsd-stable@FreeBSD.org X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 11 Oct 2012 06:30:37 -0000 Alexander Motin wrote this message on Thu, Oct 11, 2012 at 01:43 +0300: > On 08.10.2012 07:02, John-Mark Gurney wrote: > >I recently put together a new machine w/ a SuperMicro H8SCM and an > >AMD Opteron 4228 HE... I've having an issue where the clock on the > >machine skips around... The wierd part is that it's very sudden when > >it happens... ntp sometimes brings it back, but it can't when the clock > >gets too far ahread (1000 seconds), ntp dies... > > > >In order to catch it happening, I ran a sleep 60 loop fetching time > >from another server that keeps time correctly via: > >while sleep 60; do echo -n h2:; nc h2 13; date; ntpdate h2.funkthat.com; > >done > > > >here are some snippits: > >h2:Sun Oct 7 17:12:54 2012^M > >Sun Oct 7 17:12:54 PDT 2012 > > 7 Oct 17:12:54 ntpdate[31036]: the NTP socket is in use, exiting > >h2:Sun Oct 7 17:13:48 2012^M > >Sun Oct 7 17:20:21 PDT 2012 > > 7 Oct 17:20:21 ntpdate[31045]: the NTP socket is in use, exiting > > > >but then ntp brings it back in sync: > >h2:Sun Oct 7 17:28:49 2012^M > >Sun Oct 7 17:35:21 PDT 2012 > > 7 Oct 17:35:21 ntpdate[31164]: the NTP socket is in use, exiting > >h2:Sun Oct 7 17:29:49 2012^M > >Sun Oct 7 17:29:49 PDT 2012 > > 7 Oct 17:29:49 ntpdate[31170]: the NTP socket is in use, exiting > > > >It happens pretty often: > >Oct 7 00:19:13 gold ntpd[3721]: time reset -785.347912 s > >Oct 7 00:46:37 gold ntpd[3721]: time reset -392.673256 s > >Oct 7 01:04:24 gold ntpd[3721]: time reset -785.346533 s > >Oct 7 15:00:59 gold ntpd[3721]: time reset -392.681720 s > >Oct 7 16:32:11 gold ntpd[3721]: time reset -392.671268 s > >Oct 7 17:29:29 gold ntpd[3721]: time reset -392.671752 s > >Oct 7 18:04:37 gold ntpd[3721]: time reset -785.346987 s > > > >but as you can see above, the time slip happens abruptly.. looks like > >a rounding error or something... > > > >I'm now reducing the sleep to 5 seconds... but as you can see the sleep > >ends a few seconds early and local time suddenly jumped forward 6 > >minutes 33 seconds... > > > >$ sysctl kern.timecounter > >kern.timecounter.fast_gettime: 1 > >kern.timecounter.tick: 1 > >kern.timecounter.choice: TSC-low(1000) ACPI-safe(850) HPET(950) i8254(0) > >dummy(-1000000) > >kern.timecounter.hardware: TSC-low > >kern.timecounter.stepwarnings: 0 > >kern.timecounter.tc.i8254.mask: 65535 > >kern.timecounter.tc.i8254.counter: 11598 > >kern.timecounter.tc.i8254.frequency: 1193182 > >kern.timecounter.tc.i8254.quality: 0 > >kern.timecounter.tc.HPET.mask: 4294967295 > >kern.timecounter.tc.HPET.counter: 3257069245 > >kern.timecounter.tc.HPET.frequency: 14318180 > >kern.timecounter.tc.HPET.quality: 950 > >kern.timecounter.tc.ACPI-safe.mask: 16777215 > >kern.timecounter.tc.ACPI-safe.counter: 4219134510 > >kern.timecounter.tc.ACPI-safe.frequency: 3579545 > >kern.timecounter.tc.ACPI-safe.quality: 850 > >kern.timecounter.tc.TSC-low.mask: 4294967295 > >kern.timecounter.tc.TSC-low.counter: 2854866610 > >kern.timecounter.tc.TSC-low.frequency: 10937740 > >kern.timecounter.tc.TSC-low.quality: 1000 > >kern.timecounter.smp_tsc: 1 > >kern.timecounter.invariant_tsc: 1 > >$ sysctl kern.eventtimer > >kern.eventtimer.choice: LAPIC(400) i8254(100) RTC(0) > >kern.eventtimer.et.LAPIC.flags: 15 > >kern.eventtimer.et.LAPIC.frequency: 100002217 > >kern.eventtimer.et.LAPIC.quality: 400 > >kern.eventtimer.et.i8254.flags: 1 > >kern.eventtimer.et.i8254.frequency: 1193182 > >kern.eventtimer.et.i8254.quality: 100 > >kern.eventtimer.et.RTC.flags: 17 > >kern.eventtimer.et.RTC.frequency: 32768 > >kern.eventtimer.et.RTC.quality: 0 > >kern.eventtimer.periodic: 0 > >kern.eventtimer.timer: LAPIC > >kern.eventtimer.activetick: 1 > >kern.eventtimer.idletick: 0 > >kern.eventtimer.singlemul: 2 > > > >I have switched my timecounter to HPET to see if things are different... > > > >Any clues? > > Mentioned switching to HPET could tell a lot about the problem. > Switching event timer also may be interesting. Since I switch to HPET, it hasn't happened at all in the last 3 days.. Should I try switching back to TSC and switching event timer? do you need any other info, or want me to try anything else? Oh, forgot to include the specific processor info in my previous email: CPU: AMD Opteron(tm) Processor 4228 HE (2800.05-MHz K8-class CPU) Origin = "AuthenticAMD" Id = 0x600f12 Family = 0x15 Model = 0x1 Stepping = 2 Features=0x178bfbff Features2=0x1e98220b AMD Features=0x2e500800 AMD Features2=0x1c9bfff,> TSC: P-state invariant, performance statistics -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."