From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:53465) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RAn8Z-0000ae-Ka for qemu-devel@nongnu.org; Mon, 03 Oct 2011 14:21:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RAn8Y-0003vl-DW for qemu-devel@nongnu.org; Mon, 03 Oct 2011 14:21:11 -0400 Received: from ihemail2.lucent.com ([135.245.0.35]:46823) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RAn8Y-0003ts-32 for qemu-devel@nongnu.org; Mon, 03 Oct 2011 14:21:10 -0400 Received: from usnavsmail2.ndc.alcatel-lucent.com (usnavsmail2.ndc.alcatel-lucent.com [135.3.39.10]) by ihemail2.lucent.com (8.13.8/IER-o) with ESMTP id p93IKsRt011273 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Mon, 3 Oct 2011 13:20:54 -0500 (CDT) Received: from umail.lucent.com (umail-ce2.ndc.lucent.com [135.3.40.63]) by usnavsmail2.ndc.alcatel-lucent.com (8.14.3/8.14.3/GMO) with ESMTP id p93IKrxo030981 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Mon, 3 Oct 2011 13:20:54 -0500 Received: from [135.185.92.148] (cabiness01-c1.ih.lucent.com [135.185.92.148]) by umail.lucent.com (8.13.8/TPES) with ESMTP id p93IKrI2001760 for ; Mon, 3 Oct 2011 13:20:53 -0500 (CDT) Message-ID: <4E89FD03.3030404@alcatel-lucent.com> Date: Mon, 03 Oct 2011 13:20:51 -0500 From: Kenton Cabiness MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Slow linux (RH5.6) guest reboot? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org In general, we have seen that during a reboot of a running guest (by issuing a 'reboot' command in the guest), the guest goes down normally, but when coming back up, during the udev phase, it takes anywhere from a few seconds to a few hours to complete that part of the boot. Then the guest seems to behave itself after that. If the guest is powered off (virsh destroy guest), then restarted (virsh create guest), then udev returns to a speedy few seconds. It seems that the longer the guest is up, the longer it takes udev (the +2 hour udev window was on a guest up for 6 days) during a guest reboot. It's always fast after a destroy/create. Does anyone have any idea what could be causing the slowness in boot and the variability of the time spent in udev? Any suggestions on where we should look? Thanks, Kenton Specifics: =========== Host OS: - RHEL 6.1 x64: (2.6.32-131.6.1.el6.x86_64) - qemu-kvm: qemu-kvm-0.12.1.2-2.160.el6_1.2.x86_64.rpm - libvirt: libvirt-0.8.7-18.el6.x86_64.rpm Guest OS: - RHEL 5.6: (2.6.18-238.19.1.el5) VM details: - 1 VM/guest on the host - VM size is 32GB ram and 10 cores (host has 36GB and 12 cores total) - virtual disk drive is a local file on a RAID 1 disk - cpu pinning set to force each virtual core to a unique core (hyperthreading is turned on) - virtio for storage and network devices - have 16 ethernet devices tied to 16 bridges mapped to 2 NICS on the host - Use of iPXE and SGA bios for VM.