From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LchUE-0002me-8c for qemu-devel@nongnu.org; Thu, 26 Feb 2009 09:45:18 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LchUC-0002jk-Ii for qemu-devel@nongnu.org; Thu, 26 Feb 2009 09:45:17 -0500 Received: from [199.232.76.173] (port=35338 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LchUC-0002jQ-5H for qemu-devel@nongnu.org; Thu, 26 Feb 2009 09:45:16 -0500 Received: from mx2.redhat.com ([66.187.237.31]:57482) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1LchUB-0003gD-Lg for qemu-devel@nongnu.org; Thu, 26 Feb 2009 09:45:15 -0500 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id n1QEjFr3027387 for ; Thu, 26 Feb 2009 09:45:15 -0500 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n1QEjE4u017854 for ; Thu, 26 Feb 2009 09:45:14 -0500 Received: from localhost (vpn-6-8.fab.redhat.com [10.33.6.8]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id n1QEjDBj030635 for ; Thu, 26 Feb 2009 09:45:13 -0500 Date: Thu, 26 Feb 2009 14:45:11 +0000 From: "Richard W.M. Jones" Subject: Re: [Qemu-devel] Hardware watchdogs (patch for discussion only) Message-ID: <20090226144511.GC14001@amd.home.annexia.org> References: <20090225233718.GA15750@amd.home.annexia.org> <20090226105106.GD22494@redhat.com> <1235658682.5894.152.camel@ecrins.fosdick.home.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1235658682.5894.152.camel@ecrins.fosdick.home.net> Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org On Thu, Feb 26, 2009 at 02:31:22PM +0000, Steve Fosdick wrote: > On Thu, 2009-02-26 at 10:51 +0000, Daniel P. Berrange wrote: > > > I think we can only support the following options > > > > - shutdown - graceful shutdown of guest via ACPI event via > > qemu_system_powerdown_request() > > I wonder how many times the guest will be healthy enough to respond to > this and how many times it will have crashed badly enough that this does > no good. [...] > Do we want to offer the guest the option of a clean shutdown if it can > still manage that and then reboot, i.e. the shutdown option but for use > case 1? The Intel 6300ESB in fact offers this possibility already. As with other high-end watchdog hardware, it can be configured to send a "pretimer interrupt". For example, if the watchdog is set to expire after 60 seconds, you can get an interrupt N seconds before this, which you can use to try a graceful shutdown. Having said that, Linux watchdog software doesn't support this feature ... Rich. -- Richard Jones, Emerging Technologies, Red Hat http://et.redhat.com/~rjones virt-df lists disk usage of guests without needing to install any software inside the virtual machine. Supports Linux and Windows. http://et.redhat.com/~rjones/virt-df/