yahoo-eng-team team mailing list archive

[Matt Riedemann <mriedem.os@xxxxxxxxx>]

Thanks for this very nicely detailed bug report, it sounds like you're
OK with your solution and this should ultimately be resolved with the
hpet blueprint in stein which you're already aware of. Given that, we'll
likely close this as part of that blueprint since I'm not sure what kind
of backportable fix we'd have for this.

** Changed in: nova
       Status: New => Fix Released

** Changed in: nova
   Importance: Undecided => Medium

** Changed in: nova
     Assignee: (unassigned) => Jack Ding (jackding)

-- 
You received this bug notification because you are a member of Yahoo!
Engineering Team, which is subscribed to OpenStack Compute (nova).
https://bugs.launchpad.net/bugs/1805087

Title:
  libvirt+KVM: High CPU usage on Windows 10 (1803) guests

Status in OpenStack Compute (nova):
  Fix Released

Bug description:
  One of our clients recently started to use Windows 10 (update 1803)
  guest instances and reported very "slow responsiveness" of those
  instances. E.g. the boot up times are in a range of minutes whereas
  older Windows instances boot up in seconds.

  After some tests with plain libvirt I cloud relate this issue to the
  following bug [1] (https://bugs.launchpad.net/qemu/+bug/1775702)

  [1] and [2] suggests to enable Libvirt hyperv features 'synic' and 'stimer':
  <features>
    <hyperv>
      <synic state='on'/>
      <stimer state='on'/>
      ...
    </hyperv>
    ...
  </features>

  However, since our on-prem environment is still running on Ocata on Ubuntu 16.04 I'm not able to use those settings on that environment. The only way to workaround that issues is enabling the 'HPET' timer:
  <clock ...>
    <timer 'hpet' present='yes'/>
    ...
  </clock>

  whereas Nova disables this by default.

  Having HPET configurable is already requested and discussed by
  blueprint [6] (https://blueprints.launchpad.net/nova/+spec/support-
  hpet-on-guest). Nevertheless, until this is available I've done a
  simple implementation of this to solve our current issues (patch
  attached)

  Hopefully this is useful for anybody facing the same issues.

  Environment
  ===========
  $> lsb_release -a
  No LSB modules are available.
  Distributor ID:	Ubuntu
  Description:	Ubuntu 16.04.5 LTS
  Release:	16.04
  Codename:	xenial

  $> dpkg -l | grep nova
  ii  nova-api                             2:15.1.3-0ubuntu1~cloud1                   all          OpenStack Compute - API frontend
  ii  nova-common                          2:15.1.3-0ubuntu1~cloud1                   all          OpenStack Compute - common files
  ii  nova-compute                         2:15.1.3-0ubuntu1~cloud1                   all          OpenStack Compute - compute node base
  ii  nova-compute-kvm                     2:15.1.3-0ubuntu1~cloud1                   all          OpenStack Compute - compute node (KVM)
  ii  nova-compute-libvirt                 2:15.1.3-0ubuntu1~cloud1                   all          OpenStack Compute - compute node libvirt support
  ii  nova-conductor                       2:15.1.3-0ubuntu1~cloud1                   all          OpenStack Compute - conductor service
  ii  nova-consoleauth                     2:15.1.3-0ubuntu1~cloud1                   all          OpenStack Compute - Console Authenticator
  ii  nova-novncproxy                      2:15.1.3-0ubuntu1~cloud1                   all          OpenStack Compute - NoVNC proxy
  ii  nova-placement-api                   2:15.1.3-0ubuntu1~cloud1                   all          OpenStack Compute - placement API frontend
  ii  nova-scheduler                       2:15.1.3-0ubuntu1~cloud1                   all          OpenStack Compute - virtual machine scheduler
  ii  python-nova                          2:15.1.3-0ubuntu1~cloud1                   all          OpenStack Compute Python libraries
  ii  python-novaclient                    2:7.1.0-0ubuntu1~cloud0                    all          client library for OpenStack Compute API - Python 2.7

  $> dpkg -l | grep qemu
  ii  ipxe-qemu                            1.0.0+git-20150424.a25a16d-1ubuntu1.2      all          PXE boot firmware - ROM images for qemu
  ii  qemu-block-extra:amd64               1:2.8+dfsg-3ubuntu2.9~cloud3               amd64        extra block backend modules for qemu-system and qemu-utils
  ii  qemu-kvm                             1:2.8+dfsg-3ubuntu2.9~cloud3               amd64        QEMU Full virtualization
  ii  qemu-system-common                   1:2.8+dfsg-3ubuntu2.9~cloud3               amd64        QEMU full system emulation binaries (common files)
  ii  qemu-system-x86                      1:2.8+dfsg-3ubuntu2.9~cloud3               amd64        QEMU full system emulation binaries (x86)
  ii  qemu-utils                           1:2.8+dfsg-3ubuntu2.9~cloud3               amd64        QEMU utilities


  References
  ==========

  [1] https://bugs.launchpad.net/qemu/+bug/1775702
  [2] https://bugzilla.redhat.com/show_bug.cgi?id=1610461
  [3] https://forum.proxmox.com/threads/high-cpu-load-for-windows-10-guests-when-idle.44531/
  [4] https://www.reddit.com/r/VFIO/comments/80p1q7/high_kvmqemu_cpu_utilization_when_windows_10/
  [5] https://askubuntu.com/questions/1033985/kvm-high-host-cpu-load-after-upgrading-vm-to-windows-10-1803
  [6] https://blueprints.launchpad.net/nova/+spec/support-hpet-on-guest
  [7] https://specs.openstack.org/openstack/nova-specs/specs/stein/approved/support-hpet-on-guest.html

To manage notifications about this bug go to:
https://bugs.launchpad.net/nova/+bug/1805087/+subscriptions