← Back to team overview

yahoo-eng-team team mailing list archive

[Bug 1804125] Re: Nova placement disregards nova aggregate metadata

 

@Jeff, yeah it's gross, and taken way too long to deal with (granted, I
don't think anyone noticed/appreciated this regression until ~queens,
about a year after it happened).

There has been discussion about how to make the aggregate filters with
the allocation_ratio metadata *work* again, discussed at the Dublin PTG:

https://etherpad.openstack.org/p/nova-ptg-rocky-placement ~L37

That solution never materialized though...

There is also this proposal:

https://review.openstack.org/#/c/544683/

Which would essentially mirror the allocation ratio metadata from the
compute host aggregates API back to placement. If you have input on that
spec please leave comments in the review - it's waylaid at this point.

** Also affects: placement-osc-plugin
   Importance: Undecided
       Status: New

** Changed in: placement-osc-plugin
       Status: New => Opinion

** Changed in: placement-osc-plugin
   Importance: Undecided => Wishlist

-- 
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/1804125

Title:
  Nova placement disregards nova aggregate metadata

Status in OpenStack Compute (nova):
  Triaged
Status in placement-osc-plugin:
  Opinion

Bug description:
  OpenStack 17.0.8 deployed via OpenStack-Ansible.

  We have a compute environment set up with several nova aggregates,
  across which we wish to configure different cpu allocation ratios.
  Setting cpu_allocation_ratio as metadata on an aggregate and invoking
  the AggregateCoreFilter scheduler filter is ineffective and hosts fail
  to schedule past the default allocation ratio for a given compute
  node; debug scheduler logs suggest that the ignored compute nodes
  never even make it into the scheduler filter list, and indeed aren't
  even listed in the host state updates that scheduler logs.

  It appears from this single comment I was able to find in another bug
  report that placement intentionally disregards aggregate metadata, and
  so excludes compute nodes that might well be capable of scheduling
  instances:

  https://bugs.launchpad.net/nova/+bug/1742827/comments/13

  Manually updating nova.conf on the affected compute nodes to set the
  intended cpu_allocation_ratio works, but means we need to set up an
  exception in our OSA config, and that hosts will not automatically
  obtain new resource allocation ratios when moved between aggregates.

  Is this intended placement behavior? If so, what's the function of
  AggregateCoreFilter, and is there a way to restore its pre-placement
  functionality?

To manage notifications about this bug go to:
https://bugs.launchpad.net/nova/+bug/1804125/+subscriptions


References