nova/releasenotes/notes/numa-rebuild-b75f9a1966f576ea.yaml
Sean Mooney f6060ab6b5 FUP for in-place numa rebuild
This patch addresses a number of typos and minor
issues raised during review of [1][2]. A summary
of the changes are corrections to typos in comments,
a correction to the exception message, an update to
the release note and the addition of debug logging.

[1] I0322d872bdff68936033a6f5a54e8296a6fb3434
[2] I48bccc4b9adcac3c7a3e42769c11fdeb8f6fd132

Related-Bug: #1804502
Related-Bug: #1763766

Change-Id: I8975e524cd5a9c7dfb065bb2dc8ceb03f1b89e7b
2019-12-19 16:11:44 -05:00

30 lines
1.5 KiB
YAML

---
fixes:
- |
An instance can be rebuilt in-place with the original image or a new
image. Instance resource usage cannot be altered during a rebuild.
Previously Nova would have ignored the NUMA topology of the new image
continuing to use the NUMA topology of the existing instance until a move
operation was performed. As Nova did not explicitly guard against
inadvertent changes to resource requests contained in a new image,
it was possible to rebuild with an image that would violate this
requirement; see `bug #1763766`_ for details. This resulted in an
inconsistent state as the instance that was running did not match the
instance that was requested. Nova now explicitly checks if a rebuild would
alter the requested NUMA topology of an instance and rejects the rebuild
if so.
.. _`bug #1763766`: https://bugs.launchpad.net/nova/+bug/1763766
- |
With the changes introduced to address `bug #1763766`_, Nova now guards
against NUMA constraint changes on rebuild. As a result the
``NUMATopologyFilter`` is no longer required to run on rebuild since
we already know the topology will not change and therefore the existing
resource claim is still valid. As such it is now possible to do an in-place
rebuild of an instance with a NUMA topology even if the image changes
provided the new image does not alter the topology which addresses
`bug #1804502`_.
.. _`bug #1804502`: https://bugs.launchpad.net/nova/+bug/1804502