From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58504) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cUHSw-00047e-HN for qemu-devel@nongnu.org; Thu, 19 Jan 2017 13:29:43 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cUHSt-0000D7-F0 for qemu-devel@nongnu.org; Thu, 19 Jan 2017 13:29:42 -0500 Received: from indium.canonical.com ([91.189.90.7]:47527) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cUHSt-0000Ct-8o for qemu-devel@nongnu.org; Thu, 19 Jan 2017 13:29:39 -0500 Received: from loganberry.canonical.com ([91.189.90.37]) by indium.canonical.com with esmtp (Exim 4.76 #1 (Debian)) id 1cUHSr-0005Lx-Qb for ; Thu, 19 Jan 2017 18:29:37 +0000 Received: from loganberry.canonical.com (localhost [127.0.0.1]) by loganberry.canonical.com (Postfix) with ESMTP id C77B82E80C6 for ; Thu, 19 Jan 2017 18:29:37 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Date: Thu, 19 Jan 2017 18:17:32 -0000 From: Francois Gouget <1174654@bugs.launchpad.net> Reply-To: Bug 1174654 <1174654@bugs.launchpad.net> Sender: bounces@canonical.com References: <20130430080722.32341.54160.malonedeb@gac.canonical.com> Message-Id: <20170119181732.20152.75495.malone@wampee.canonical.com> Errors-To: bounces@canonical.com Subject: [Qemu-devel] [Bug 1174654] Re: qemu-system-x86_64 takes 100% CPU after host machine resumed from suspend to ram List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org This sounds sort of like a problem I have with reverting to live snapshots. What I found out is that this is related to restoring the clock in the gues= t. You can find out more about it there: https://bugs.launchpad.net/qemu/+bug/1505041 The takeaway is that a workaround is to set track=3D'guest' on the rtc timer. For instance: If you have track=3D'catchup' QEMU seems to try to send millions of interrupts so the guest clock will catch up to the current time, which can take minutes during which the guest is unusable. It is possible this no longer happens though as I have had this workaround in place for quite some time but nobody formally said this is fixed or pointed to a commit fixing this. -- = You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1174654 Title: qemu-system-x86_64 takes 100% CPU after host machine resumed from suspend to ram Status in QEMU: Confirmed Status in qemu package in Ubuntu: Invalid Bug description: I have Windows XP SP3 inside qemu VM. All works fine in 12.10. But after upgraiding to 13.04 i have to restart the VM each time i resuming my host machine, because qemu process starts to take CPU cycles and OS inside VM is very slow and sluggish. However it's still controllable and could be shutdown by itself. According to the taskmgr any active process takes 99% CPU. It's not stuck on some single process. To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1174654/+subscriptions