Kashyap Chamarthy
fc4794acc6
Upstream Linux kernel has deleted[*] the `perf` framework integration with Intel CMT (Cache Monitoring Technology; or "CQM" in Linux kernel parlance), because the feature was broken by design -- an incompatibility between Linux's `perf` infrastructure and Intel CMT hardware support. It was removed in upstream kernel version v4.14; but bear in mind that downstream Linux distributions with lower kernel versions than 4.14 have backported the said change. Nova supports monitoring of the above mentioned Intel CMT events (namely: 'cmt', 'mbm_local', and 'mbm_total') via the configuration attribute `[libvirt]/enabled_perf_events`. Given that the underlying Linux kernel infrastructure for Intel CMT is removed, we should remove support for it in Nova too. Otherwise enabling them in Nova, and updating to a Linux kernel 4.14 (or above) will result in instances failing to boot. To that end, deprecate support for the three Intel CMT events in "Rocky" release, with the intention to remove support for it in the upcoming "Stein" release. Note that we cannot deprecate / remove `enabled_perf_events` config attribute altogether -- since there are other[+] `perf` events besides Intel CMT. Whether anyone is using those other events with Nova is a good question to which we don't have an equally good answer for, if at all. [*] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c39a0e2 [+] https://libvirt.org/formatdomain.html#elementsPerf Closes-Bug: #1751073 Change-Id: I7e77f87650d966d605807c7be184e670259a81c1 Signed-off-by: Kashyap Chamarthy <kchamart@redhat.com>
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Team and repository tags
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.. image:: https://governance.openstack.org/tc/badges/nova.svg
:target: https://governance.openstack.org/tc/reference/tags/index.html
.. Change things from this point on
OpenStack Nova
==============
OpenStack Nova provides a cloud computing fabric controller, supporting a wide
variety of compute technologies, including: libvirt (KVM, Xen, LXC and more),
Hyper-V, VMware, XenServer, OpenStack Ironic and PowerVM.
Use the following resources to learn more.
API
---
To learn how to use Nova's API, consult the documentation available online at:
- `Compute API Guide <https://developer.openstack.org/api-guide/compute/>`__
- `Compute API Reference <https://developer.openstack.org/api-ref/compute/>`__
For more information on OpenStack APIs, SDKs and CLIs in general, refer to:
- `OpenStack for App Developers <https://www.openstack.org/appdev/>`__
- `Development resources for OpenStack clouds
<https://developer.openstack.org/>`__
Operators
---------
To learn how to deploy and configure OpenStack Nova, consult the documentation
available online at:
- `OpenStack Nova <https://docs.openstack.org/nova/>`__
In the unfortunate event that bugs are discovered, they should be reported to
the appropriate bug tracker. If you obtained the software from a 3rd party
operating system vendor, it is often wise to use their own bug tracker for
reporting problems. In all other cases use the master OpenStack bug tracker,
available at:
- `Bug Tracker <https://bugs.launchpad.net/nova>`__
Developers
----------
For information on how to contribute to Nova, please see the contents of the
CONTRIBUTING.rst.
Any new code must follow the development guidelines detailed in the HACKING.rst
file, and pass all unit tests.
Further developer focused documentation is available at:
- `Official Nova Documentation <https://docs.openstack.org/nova/>`__
- `Official Client Documentation
<https://docs.openstack.org/python-novaclient/>`__
Other Information
-----------------
During each `Summit`_ and `Project Team Gathering`_, we agree on what the whole
community wants to focus on for the upcoming release. The plans for nova can
be found at:
- `Nova Specs <http://specs.openstack.org/openstack/nova-specs/>`__
.. _Summit: https://www.openstack.org/summit/
.. _Project Team Gathering: https://www.openstack.org/ptg/