← Back to team overview

yahoo-eng-team team mailing list archive

[Bug 1978489] Re: libvirt / cgroups v2: cannot boot instance with more than 16 CPUs

 

Re:

> The same patch should also be available on cloud archive cloud:focal-
yoga

This will happen alongside the changes being made into 22.04 - the
updates are in the yoga-proposed pocket at the moment.

** Also affects: cloud-archive
   Importance: Undecided
       Status: New

** Also affects: cloud-archive/yoga
   Importance: Undecided
       Status: New

** Changed in: cloud-archive
       Status: New => Invalid

** Changed in: cloud-archive/yoga
       Status: New => Fix Committed

** Changed in: cloud-archive/yoga
   Importance: Undecided => High

** Changed in: nova (Ubuntu Jammy)
   Importance: Undecided => High

-- 
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/1978489

Title:
  libvirt / cgroups v2: cannot boot instance with more than 16 CPUs

Status in Ubuntu Cloud Archive:
  Invalid
Status in Ubuntu Cloud Archive yoga series:
  Fix Committed
Status in OpenStack Compute (nova):
  In Progress
Status in nova package in Ubuntu:
  Confirmed
Status in nova source package in Jammy:
  Fix Committed

Bug description:
  Description
  ===========

  Using the libvirt driver and a host OS that uses cgroups v2 (RHEL 9,
  Ubuntu Jammy), an instance with more than 16 CPUs cannot be booted.

  Steps to reproduce
  ==================

  1. Boot an instance with 10 (or more) CPUs on RHEL 9 or Ubuntu Jammy
  using Nova with the libvirt driver.

  Expected result
  ===============

  Instance boots.

  Actual result
  =============

  Instance fails to boot with a 'Value specified in CPUWeight is out of
  range' error.

  Environment
  ===========

  Originially report as a libvirt but in RHEL 9 [1]

  Additional information
  ======================

  This is happening because Nova defaults to 1024 * (# of CPUs) for the
  value of domain/cputune/shares in the libvirt XML. This is then passed
  directly by libvirt to the cgroups API, but cgroups v2 has a maximum
  value of 10000. 10000 / 1024 ~= 9.76

  [1] https://bugzilla.redhat.com/show_bug.cgi?id=2035518

  
  ====================================

  Ubuntu SRU Details:

  [Impact]
  See above.

  [Test Case]
  See above.

  [Regression Potential]
  We've had this change in other jammy-based versions of the nova package for a while now, including zed, antelope, bobcat.

To manage notifications about this bug go to:
https://bugs.launchpad.net/cloud-archive/+bug/1978489/+subscriptions



References