From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Thomason Subject: Guest Hang Bugs Date: Wed, 14 Jan 2009 11:17:07 -0800 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit To: Return-path: Received: from multiply.divide.org ([207.218.248.89]:53454 "EHLO multiply.divide.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753976AbZANTXS (ORCPT ); Wed, 14 Jan 2009 14:23:18 -0500 Received: from [10.255.255.212] (65-115-68-195.dia.static.qwest.net [65.115.68.195]) (using TLSv1 with cipher DES-CBC3-SHA (168/168 bits)) (No client certificate requested) by multiply.divide.org (Postfix) with ESMTP id BF93645127 for ; Wed, 14 Jan 2009 11:15:30 -0800 (PST) Sender: kvm-owner@vger.kernel.org List-ID: Hello, I am able to reliably reproduce a condition where a guest goes into a tight loop or spinlock on all running cores. The scenario is exactly as described in bug 2351676, though my environment differs as detailed below. My observation is that the issue is correlated to the number of VCPUs assigned to the guest and CPU load. The higher the number of VCPUs and CPU utilization, the more easily it is triggered. If a KVM developer is interested in debugging live, I might be able to arrange getting the system in question into a DMZ. A review of the kvm tracker leads me to believe that the following bugs are possibly related: [ 2351676 ] Guests hang periodically on Ubuntu-8.10 [ 2353811 ] Solaris 10 guest unstable [ 2494730 ] Guests "stalling" on kvm-82 [ 2138079 ] kvm locks up system [ 2113643 ] guests AND host still getting stuck under CPU load KVM Host Configuration: 4 x Quad-Core AMD Opteron Processors (8346 HE @ 1.8Ghz) 64GB DDR2 667Mhz Fedora 10 x64 Kernel 2.6.28 KVM-82 KVM Guest Configuration: 32GB Memory 1 to 16 VCPUs Centos 5.2 x64 Kernel 2.6.28 IDE disk e1000 NIC Regards, James