Attaching virtual GPU devices to guests in nova - libvirt reshaping

[Matt Riedemann]

- [x] This is a doc addition request.

This is coming up from discussion about what to document in the release notes for the libvirt VGPU reshaper work that happened in Stein:

https://review.openstack.org/#/c/644412/4/releasenotes/notes/stein-prelude-b5fe92310e1e725e.yaml@57

Specifically about the upgrade impact of VGPU inventory and allocations moving from the root compute node resource provider to a child resource provider.

The release notes and docs for VGPUs are not very clear about this change (the docs don't actually mention anything about it). So this bug is for tracking that gap.

I think it would be good to at the very least mention that starting in the Stein release, VGPU inventory and allocations are tracked on a child resource provider of the root compute node resource provider. And we could illustrate this using examples from openstack CLIs:

https://docs.openstack.org/osc-placement/latest/index.html

For example, list resource providers where there are two, one for the root compute node resource provider and one for a VGPU provider. Then list inventories on each and see there is VCPU/MEMORY_MB/DISK_GB on the compute node root provider and VGPU inventory on the child provider. Nothing fancy but something as a way to show, if you set this up correctly and things are working correctly, this is what you should expect to see.

-----------------------------------
Release: 18.1.0.dev1645 on 2019-02-27 13:28:37
SHA: 592658aafcb5de8d31b19c8833a8d41ca86a5654
Source: https://git.openstack.org/cgit/openstack/nova/tree/doc/source/admin/virtual-gpu.rst
URL: https://docs.openstack.org/nova/latest/admin/virtual-gpu.html

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/647519

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/647519
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=44490142be5c20389703aeed54edca28f27c43c0
Submitter: Zuul
Branch: master

commit 44490142be5c20389703aeed54edca28f27c43c0
Author: Sylvain Bauza <email address hidden>
Date: Mon Mar 25 16:54:18 2019 +0100

    Add doc on VGPU allocs and inventories for nrp

    Now that we reshape inventories and allocations for VGPU resources in Stein,
    we think it's good for operators to know how to verify the resources using
    osc-placement.

    Change-Id: Ic58709aac2dd1f20f1b8440a3cea4f29eed9a965
    Closes-Bug: #1821015

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/stein
Review: https://review.openstack.org/649454

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/649454
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=0fd77f3f658ea3b6e44a7c446f95be9d4c8c8b13
Submitter: Zuul
Branch: stable/stein

commit 0fd77f3f658ea3b6e44a7c446f95be9d4c8c8b13
Author: Sylvain Bauza <email address hidden>
Date: Mon Mar 25 16:54:18 2019 +0100

    Add doc on VGPU allocs and inventories for nrp

    Now that we reshape inventories and allocations for VGPU resources in Stein,
    we think it's good for operators to know how to verify the resources using
    osc-placement.

    Change-Id: Ic58709aac2dd1f20f1b8440a3cea4f29eed9a965
    Closes-Bug: #1821015
    (cherry picked from commit 44490142be5c20389703aeed54edca28f27c43c0)

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/nova 19.0.0.0rc2 release candidate.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/nova 20.0.0.0rc1 release candidate.