Ignore threads_per_core for unsupported machine types in vm-instance

[kkr16]

Description

Adds a condition to the advanced_machine_features block in the vm-instance module that is used to bypass the threads_per_core parameter for machine types that do not support setting an SMT parameter (t2d instances, shared core instances, and instances with <2 vCPU).

The default threads_per_core has been set to 0, which translates to an intelligent default behavior that turns off SMT on supported machine types, and removes the parameter where it is not supported.

To test, test_configs/threads_per_core.yaml has been expanded to include more machine types, and threads_per_core=null, and threads_per_core=0.

Submission Checklist

• Have you installed and run this change against pre-commit? (pre-commit install)
• Are all tests passing? (make tests)
• Have you written unit tests to cover this change?
• Is unit test coverage still above 80%?
• Have you updated all applicable documentation?
• Have you followed the guidelines in our Contributing document?

[tpdownes]

/gcbrun

[tpdownes]

@kkr16 does this merit review now?

Please edit the PR to target the develop branch. You may need to rebase. All PRs initially land on develop before release.

[kkr16]

@kkr16 does this merit review now?

No, @nick-stroud and I had a chat on the target behavior. I'll push a change accordingly.

Please edit the PR to target the develop branch. You may need to rebase. All PRs initially land on develop before release.

Will do. Thanks!

[tpdownes]

Please squash these commits as advised in #411

[kkr16]

Please squash these commits as advised in #411

Done. Thanks!

[tpdownes]

/gcbrun

[nick-stroud]

@kkr16, I just had a few "nits". For context, "nits" are suggestions that, in my opinion, would improve the code but are not required for my approval. It is your choice whether or not to accept these suggestions.

If you want to decline the suggestions, then just respond "Ack." to the comment and resolve the thread. This just lets me know that you saw it and are not going to act on it. If you do make any of the suggested changes then I would just add it as one additional commit titled something like "Addressing feedback". Either way once you are done I will approve and merge.

[nick-stroud]

/gcbrun