@william, Yes, please boot into the broken kernel and run apport-collect 1344430.
-- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1344430 Title: 10-15% iowait on kvm instances on Ubuntu 14.04 Status in “linux” package in Ubuntu: Confirmed Bug description: After upgrading from Ubuntu 12.04 to Ubuntu 14.04 we began seeing 10-15% iowait on kvm guests. The guests had little to no load and yet the shell was laggy and commands took forever to respond (assuming you could even type them) # uname -a Linux kvm-andromeda 3.13.0-29-generic #53-Ubuntu SMP Wed Jun 4 21:00:20 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux # kvm --version QEMU emulator version 2.0.0 (Debian 2.0.0+dfsg-2ubuntu1.1), Copyright (c) 2003-2008 Fabrice Bellard I posted to Ubuntu Server and they suggested that I upgrade my kernel version. Relevant Mailing List discussion: https://lists.ubuntu.com/archives/ubuntu-server/2014-July/006925.html After installing a 3.14 kernel the performance returned to normal. kvm-andromeda:~# uname -a Linux kvm-andromeda 3.14.1-031401-generic #201404141220 SMP Mon Apr 14 16:21:48 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux --- ApportVersion: 2.14.1-0ubuntu3.2 Architecture: amd64 DistroRelease: Ubuntu 14.04 Package: linux (not installed) ProcEnviron: TERM=screen PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/bash Tags: trusty Uname: Linux 3.14.1-031401-generic x86_64 UnreportableReason: The running kernel is not an Ubuntu kernel UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: root _MarkForUpload: True To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1344430/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
