From mboxrd@z Thu Jan 1 00:00:00 1970 From: Juergen Gross Subject: Re: Dom0 losing interrupts??? Date: Mon, 14 Feb 2011 10:38:40 +0100 Message-ID: <4D58F820.80401@ts.fujitsu.com> References: <4D58D2D7.9010803@ts.fujitsu.com> <4D59034A0200007800031B7A@vpn.id2.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4D59034A0200007800031B7A@vpn.id2.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Jan Beulich Cc: "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org On 02/14/11 10:26, Jan Beulich wrote: >>>> On 14.02.11 at 07:59, Juergen Gross wrote: >> I used xen-unstable, kernel 2.6.32.24 from SLES11 SP1 on a 12 core INTEL >> nehalem machine. I pinned all 12 Dom0 vcpus to pcpu 1-2 and started a >> parallel >> build. After about 2 minutes the first missing interrupts were reported, a >> little bit later the next one, no xen messages are printed: > > That's certainly not too surprising, somewhat depending on the > maximally tolerated latencies. It seems unlikely to me for a 6-fold > CPU over-commit to promise stable operation, yet certain > adjustments could probably be done to make it work better (like > temporarily boosting the priority of a hardware interrupt's target > vCPU). I would understand timeouts. But shouldn't the interrupt come in sooner or later? At least the megasas driver seems not to be able to recover from this problem, as a result my root filesystem is set to read-only... This would mean there is a problem in the megasas driver, correct? And Andre reports stability problems of his machine in similar cases, but in his case the network driver seems to be the reason. Are you planning to prepare a patch for boosting the priority of vcpus being the target for a hardware interrupt? I think I would have to search some time to find the correct places to change... Juergen -- Juergen Gross Principal Developer Operating Systems TSP ES&S SWE OS6 Telephone: +49 (0) 89 3222 2967 Fujitsu Technology Solutions e-mail: juergen.gross@ts.fujitsu.com Domagkstr. 28 Internet: ts.fujitsu.com D-80807 Muenchen Company details: ts.fujitsu.com/imprint.html