From owner-freebsd-stable@FreeBSD.ORG Wed Apr 6 10:48:08 2005 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2231716A4CE for ; Wed, 6 Apr 2005 10:48:08 +0000 (GMT) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9522C43D58 for ; Wed, 6 Apr 2005 10:48:06 +0000 (GMT) (envelope-from avg@icyb.net.ua) Received: from [212.40.38.87] (oddity-e.topspin.kiev.ua [212.40.38.87]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id NAA01840; Wed, 06 Apr 2005 13:45:47 +0300 (EEST) (envelope-from avg@icyb.net.ua) Message-ID: <4253BDDB.3060805@icyb.net.ua> Date: Wed, 06 Apr 2005 13:45:47 +0300 From: Andriy Gapon User-Agent: Mozilla Thunderbird 1.0.2 (X11/20050328) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Andriy Gapon References: <1112365401.00269464.1112352602@10.7.7.3> <1112372627.00269546.1112361001@10.7.7.3> <1112372655.00269555.1112362202@10.7.7.3> <424D7911.8060805@icyb.net.ua> <6.2.0.14.2.20050401183743.04813c10@gid.co.uk> <42527E03.5090805@icyb.net.ua> <20050405193226.GB84293@cirb503493.alcatel.com.au> <42539A3C.7070807@icyb.net.ua> In-Reply-To: <42539A3C.7070807@icyb.net.ua> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit cc: Peter Jeremy cc: David Magda cc: stable@freebsd.org Subject: Re: Kernel NTP flipping between FLL and PLL modes X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 06 Apr 2005 10:48:08 -0000 on 06.04.2005 11:13 Andriy Gapon said the following: > I am using the default value of maxpoll, no overrides. > So, IMO this leaves one possibility: mtemp > 2048, i.e. hardupdate() was > not called for longer than this time i.e. either ntp_adjtime() was not > called or it was called without MOD_OFFSET. > It looks like it is not trivial to find the cause of this. > I can not explain it, but I've suddenly got a gut feeling that the subject discussed might be a result of revision 1.53 of sys/kern/kern_ntptime.c Deal with MOD_FREQUENCY before MOD_OFFSET because the latter is the one which runs the actual update. This fixes a bug where there were a delay in applying the frequency adjustment. In extreme cases this could result in marginal stability of the kernel-pll. I can test this hypothesis as soon as I get a chance to reboot the machine in question (might not be soon). -- Andriy Gapon