From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.92] helo=mail.sourceforge.net) by sc8-sf-list1-new.sourceforge.net with esmtp (Exim 4.43) id 1Jq7oR-0005x6-Os for user-mode-linux-devel@lists.sourceforge.net; Sun, 27 Apr 2008 07:25:08 -0700 Received: from 41-052.adsl.zetnet.co.uk ([194.247.41.52] helo=mail.esperi.org.uk ident=user55488) by mail.sourceforge.net with esmtp (Exim 4.44) id 1Jq7oQ-00057C-23 for user-mode-linux-devel@lists.sourceforge.net; Sun, 27 Apr 2008 07:25:07 -0700 Received: from esperi.org.uk (nix@hades.wkstn.nix [192.168.14.18]) by mail.esperi.org.uk (8.12.11.20060614/8.12.11) with ESMTP id m3RE3mkk000427 for ; Sun, 27 Apr 2008 15:03:48 +0100 References: <877iel7ljp.fsf@hades.wkstn.nix> <87ve256146.fsf@hades.wkstn.nix> <871w4sqxgv.fsf@hades.wkstn.nix> From: Nix Date: Sun, 27 Apr 2008 15:02:33 +0100 In-Reply-To: <871w4sqxgv.fsf@hades.wkstn.nix> (nix@esperi.org.uk's message of "Sat, 26 Apr 2008 19:31:44 +0100") Message-ID: <87wsmjbdl2.fsf@hades.wkstn.nix> MIME-Version: 1.0 Subject: Re: [uml-devel] actually useful backtrace from a CPU-chewing hang List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: user-mode-linux-devel-bounces@lists.sourceforge.net Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net To: Jeff Dike Cc: user-mode-linux-devel@lists.sourceforge.net On 26 Apr 2008, nix@esperi.org.uk uttered the following: > On 25 Apr 2008, nix@esperi.org.uk uttered the following: > >> On 25 Apr 2008, nix@esperi.org.uk told this: >> >>> I suspect this can go wrong anywhere, but it happens to have been a >>> CBQ-triggered gettimeofday() while sending an arp that did it. (My ADSL >>> router pretty much bombs the poor damn machine with ARP packets all the >>> time.) >> >> Woo, it's happening a lot tonight. > > The cause of this is almost certainly time-skewing on the *host* via > adjtimex(). I stopped ntpd and there were no problems for half a day: I > restarted it, and as soon as ntpd had synched and begun slewing the time > (within a second of slewing beginning, probably less than that), *wham*: Time-stepping on the host is enough to cause trouble. I switched to using ntpdate -b to keep time in synch, and since then my UML instances have gone into mad loops only on the hour, when the ntpdate time-step should take place. -- `If you are having a "ua luea luea le ua le" kind of day, I can only assume that you are doing no work due [to] incapacitating nausea caused by numerous lazy demons.' --- Frossie ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel