From owner-freebsd-stable@FreeBSD.ORG Sun Feb 21 09:02:30 2010 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 496A11065670 for ; Sun, 21 Feb 2010 09:02:30 +0000 (UTC) (envelope-from torfinn.ingolfsen@broadpark.no) Received: from bgo1smout1.broadpark.no (bgo1smout1.broadpark.no [217.13.4.94]) by mx1.freebsd.org (Postfix) with ESMTP id F354F8FC18 for ; Sun, 21 Feb 2010 09:02:29 +0000 (UTC) MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-type: text/plain; charset=US-ASCII Received: from bgo1sminn1.broadpark.no ([217.13.4.93]) by bgo1smout1.broadpark.no (Sun Java(tm) System Messaging Server 6.3-3.01 (built Jul 12 2007; 32bit)) with ESMTP id <0KY600I3FP3X3L50@bgo1smout1.broadpark.no> for freebsd-stable@freebsd.org; Sun, 21 Feb 2010 10:02:21 +0100 (CET) Received: from kg-v2.kg4.no ([80.203.92.186]) by bgo1sminn1.broadpark.no (Sun Java(tm) System Messaging Server 6.3-3.01 (built Jul 12 2007; 32bit)) with SMTP id <0KY6004RFP3X7LB0@bgo1sminn1.broadpark.no> for freebsd-stable@freebsd.org; Sun, 21 Feb 2010 10:02:21 +0100 (CET) Date: Sun, 21 Feb 2010 10:02:21 +0100 From: Torfinn Ingolfsen To: freebsd-stable@freebsd.org Message-id: <20100221100221.e6809b9e.torfinn.ingolfsen@broadpark.no> In-reply-to: <20100221050823.GB22670@server.vk2pj.dyndns.org> References: <20100212132947.eb2af3d0.torfinn.ingolfsen@broadpark.no> <20100212131117.GA51905@icarus.home.lan> <20100212174452.2140cd72.torfinn.ingolfsen@broadpark.no> <20100217194927.e3ec60ae.torfinn.ingolfsen@broadpark.no> <20100217200322.da66c9f8.torfinn.ingolfsen@broadpark.no> <20100218205458.GA78560@server.vk2pj.dyndns.org> <20100218231223.ec6b9fa8.torfinn.ingolfsen@broadpark.no> <20100219003844.acdaa866.torfinn.ingolfsen@broadpark.no> <20100220015351.GB81639@server.vk2pj.dyndns.org> <20100220223201.178e67dd.torfinn.ingolfsen@broadpark.no> <20100221050823.GB22670@server.vk2pj.dyndns.org> X-Mailer: Sylpheed 2.7.1 (GTK+ 2.18.7; amd64-portbld-freebsd8.0) X-Face: "t9w2,-X@O^I`jVW\sonI3.,36KBLZE*AL[y9lL[PyFD*r_S:dIL9c[8Y>V42R0"!"yb_zN,f#%.[PYYNq; m"_0v; ~rUM2Yy!zmkh)3&U|u!=T(zyv,MHJv"nDH>OJ`t(@mil461d_B'Uo|'nMwlKe0Mv=kvV?Nh@>Hb<3s_z2jYgZhPb@?Wi^x1a~Hplz1.zH Subject: Re: ntpd struggling to keep up - how to fix? X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 21 Feb 2010 09:02:30 -0000 On Sun, 21 Feb 2010 16:08:23 +1100 Peter Jeremy wrote: > That's definitely not good - though it's marginally better than before. > I have checked on a local machine and the timecounter frequency definitely > needs to be adjusted in the opposite direction to the ntpd drift. > > I think I see the problem: I suggested 3579545Hz - 2500ppm, which > gives an ACPI frequency of 3570596Hz. There was some miscommunication > and you have set an ACPI frequency of 3577045Hz which is 2500Hz (or > 698ppm) lower. The drift reported by the time resets has gone from > +1930ppm (14.5s in 2:05:17) to +1233ppm (8.4s in 2:20:06) - which is > 697ppm - fairly close to the change you made. (The PLL is running > at +500ppm so the actual clock offset is 500ppm more than the "time > reset" reports suggest. Very good info, it helps me understand more. Thanks! > Having re-checked my maths, using both your "time reset" results, can > you please try: > sysctl machdep.acpi_timer_freq=3570847 Ok, trying that now: root@kg-f2# sysctl machdep.acpi_timer_freq=3570847 machdep.acpi_timer_freq: 3577045 -> 3570847 root@kg-f2# /etc/rc.d/ntpd stop Stopping ntpd. root@kg-f2# rm /var/db/ntpd.drift root@kg-f2# /etc/rc.d/ntpd start Starting ntpd. > That should result in a drift of close to zero (well within NTP's > lock range of +/- 300ppm). Good. > No. Once ntpd decides to continuously step, something is broken. Aha, very good to know. -- Torfinn