Add CPUManager policy option to restrict reservedSystemCPUs to system daemons and interrupt processing

[jingczhang]

Enhancement Description

• One-line enhancement description (can be used as a release note):
  Add CPUManager policy option to restrict reservedSystemCPUs to system daemons and interrupt processing

• Kubernetes Enhancement Proposal:
  https://github.com/kubernetes/enhancements/blob/master/keps/sig-node/4540-strict-cpu-reservation/README.md

• Discussion Link:
  Feature: Add StrictCPUReservation option in static cpu policy kubernetes#103933

• Primary contact (assignee):
  @jingczhang

• Responsible SIGs:
  /sig node

• Enhancement target (which target equals to which milestone):

  • Alpha release target (1.32):
  • Beta release target (1.33):
  • Stable release target (1.35):

• Alpha

  • KEP (k/enhancements) update PR(s): KEP-4540: Add CPUManager policy option to restrict reservedSystemCPUs to system daemons and interrupt processing #4540 #4541
  • Code (k/k) update PR(s): KEP-4540: Add CPUManager policy option to restrict reservedSystemCPUs to system daemons and interrupt processing kubernetes#127483 and node: metrics: add metrics about cpu pool sizes kubernetes#127506
  • Docs (k/website) update PR(s): KEP-4540: CPUManager strict-cpu-reservation policy option documentation website#48356 and KEP-4540: CPUManager strict-cpu-reservation policy option blog website#48371

• Beta

  • KEP (k/enhancements) update PR(s): KEP-4540: Move to beta #5128
  • Code (k/k) update PR(s): KEP-4540: strict-cpu-reservation beta kubernetes#130290
  • Docs (k/website) update(s): Mark strict-cpu-reservation as beta website#49902

Please keep this description up to date. This will help the Enhancement Team to track the evolution of the enhancement efficiently.

[ffromani]

Hi, thanks for filing the issue. Unfortunately the 1.30 release is already in code freeze, so the earliest possible version is 1.31.

[jingczhang]

Added KEP PR link; changed release targets as adviced.

[k8s-triage-robot]

The Kubernetes project currently lacks enough contributors to adequately respond to all issues.

This bot triages un-triaged issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
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You can:

• Mark this issue as fresh with /remove-lifecycle stale
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Please send feedback to sig-contributor-experience at kubernetes/community.

/lifecycle stale

[ffromani]

/remove-lifecycle stale

we're quite active here

[k8s-triage-robot]

The Kubernetes project currently lacks enough contributors to adequately respond to all issues.

This bot triages un-triaged issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Mark this issue as fresh with /remove-lifecycle stale
• Close this issue with /close
• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/lifecycle stale

[haircommander]

/remove-lifecycle stale

[haircommander]

/milestone v1.32
/label lead-opted-in

[tjons]

Hello @jingczhang 👋, Enhancements team here.

Just checking in as we approach enhancements freeze on 02:00 UTC Friday 11th October 2024 / 19:00 PDT Thursday 10th October 2024.

This enhancement is targeting stage alpha for v1.32 (correct me, if otherwise)

Here's where this enhancement currently stands:

• KEP readme using the latest template has been merged into the k/enhancements repo.
• KEP status is marked as implementable for latest-milestone: v1.32.
• KEP readme has up-to-date graduation criteria
• KEP has a production readiness review that has been completed and merged into k/enhancements. (For more information on the PRR process, check here). If your production readiness review is not completed yet, please make sure to fill the production readiness questionnaire in your KEP by the PRR Freeze deadline on Thursday 3rd October 2024 so that the PRR team has enough time to review your KEP.

For this KEP, we would just need to update the following:

• Merge https://github.com/kubernetes/enhancements/pull/4541/files. The status must be set to implementable in the kep.yaml file.
• KEP has a production readiness review that has been completed and merged into k/enhancements.

The status of this enhancement is marked as at risk for enhancement freeze. Please keep the issue description up-to-date with appropriate stages as well.

If you anticipate missing enhancements freeze, you can file an exception request in advance. Thank you!

[ffromani]

@jingczhang need to opt in the Production Readiness Review (PRR) flow, the deadline is tomorrow Oct 3, 2024. Just opting in is required, the actual review will happen later.
You need to add an extra yaml file prod-readiness/sig-node/4540.yaml whose content would be something like

kep-number: 4800
alpha:
  approver: "@soltysh"

example: https://github.com/kubernetes/enhancements/blob/4ef0377fca621dcd080d2757ba7ba4cde1f26b77/keps/prod-readiness/sig-node/4800.yaml

I think you can start adding @soltysh as approver, the PRR team will suggest rebalancing with different approver as they see fit.

EDIT: another example: https://github.com/kubernetes/enhancements/blob/2626c678b2c62b6814c0a73ce4c0e276dcdbed1e/keps/prod-readiness/sig-windows/4885.yaml

(note the above example is sig-windows, you will need to use sig-node)

[fykaa]

Hello @jingczhang 👋, v1.33 Enhancements team here.

Just checking in as we approach enhancements freeze on 02:00 UTC Friday 14th February 2025 / 19:00 PDT Thursday 13th February 2025.

This enhancement is targeting stage beta for v1.33 (correct me, if otherwise)
/stage beta

Here's where this enhancement currently stands:

• KEP readme using the latest template has been merged into the k/enhancements repo.
• KEP status is marked as implementable for latest-milestone: v1.33.
• KEP readme has up-to-date graduation criteria
• KEP has a production readiness review that has been completed and merged into k/enhancements. (For more information on the PRR process, check here). If your production readiness review is not completed yet, please make sure to fill the production readiness questionnaire in your KEP by the PRR Freeze deadline on Thursday 6th February 2025 so that the PRR team has enough time to review your KEP.

For this KEP, we would just need to update the following:

• Ensure that the KEP has undergone a production readiness review and has been merged into k/enhancements.

The status of this enhancement is marked as At risk for enhancements freeze. Please keep the issue description up-to-date with appropriate stages as well.

If you anticipate missing enhancements freeze, you can file an exception request in advance. Thank you!

[swatisehgal]

Please update the issue description with the link to the PR (with KEP updates) for graduation to Beta.

[dipesh-rawat]

Hi @jingczhang 👋, 1.33 Enhancements team here,

Just a quick friendly reminder as we approach the enhancements freeze later this week, at 02:00 UTC Friday 14th February 2025 / 19:00 PDT Thursday 13th February 2025.

The current status of this enhancement is marked as At risk for enhancement freeze. There are a few requirements mentioned in the comment #4540 (comment) that still need to be completed.

If you anticipate missing enhancements freeze, you can file an exception request in advance. Thank you!

[dipesh-rawat]

Hello @jingczhang 👋, 1.33 Enhancements team here.

Now that PR #5128 has been merged, all the KEP requirements are in place and merged into k/enhancements, this enhancement is all good for the upcoming enhancements freeze. 🚀

The status of this enhancement is marked as tracked for enhancement freeze. Please keep the issue description up-to-date with appropriate stages as well. Thank you!
(cc: @fykaa)

/label tracked/yes

[rayandas]

Hello @jingczhang 👋, v1.33 Docs Lead here.

Does this enhancement work planned for v1.33 require any new docs or modification to existing docs?

If so, please follow the steps here to open a PR against dev-1.33 branch in the k/website repo. This PR can be just a placeholder at this time and must be created before Thursday 27th February 2025 18:00 PDT.

Also, take a look at Documenting for a release to get yourself familiarize with the docs requirement for the release.

Thank you!

[jingczhang]

Hi @rayandas, I have created the doc PR kubernetes/website#49902 which changes the feature status from alpha to beta.

[rayandas]

Thanks @jingczhang

[fykaa]

Hey again @jingczhang 👋, v1.33 Enhancements team here,

Just checking in as we approach Code Freeze at 02:00 UTC Friday 21st March 2025 / 19:00 PDT Thursday 20th March 2025.

Here's where this enhancement currently stands:

• All PRs to the Kubernetes repo that are related to your enhancement are linked in the above issue description (for tracking purposes).
• All PRs are ready to be merged (they have approved and lgtm labels applied) by the code freeze deadline. This includes tests.

For this enhancement, it looks like the following PRs need to be merged before code freeze (and we need to update the Issue description to include all the related PRs of this KEP):

• KEP-4540: strict-cpu-reservation beta kubernetes#130290

If you anticipate missing code freeze, you can file an exception request in advance.

Also, please let me know if there are other PRs in k/k we should be tracking for this KEP.

The status of this enhancement is marked as At risk for code freeze.

As always, we are here to help if any questions come up. Thanks!

[Udi-Hofesh]

Hey @jingczhang 👋 -- this is Udi (@Udi-Hofesh) from the 1.33 Communications Team!

For the 1.33 release, we are currently in the process of collecting and curating a list of potential feature blogs, and we'd love for you to consider writing one for your enhancement!

As you may be aware, feature blogs are a great way to communicate to users about features that fall into (but are not limited to) the following categories:

• This introduces some breaking change(s)
• This has significant impacts and/or implications to users
• ...Or this is a long-awaited feature, which would go a long way to cover the journey more in detail 🎉

To opt in to write a feature blog, could you please let us know and open a "Feature Blog placeholder PR" (which can be only a skeleton at first) against the website repository by Wednesday, 5th March, 2025? For more information about writing a blog, please find the blog contribution guidelines 📚

Tip

Some timelines to keep in mind:

• 02:00 UTC Wednesday, 5th March, 2025: Feature blog PR freeze
• Monday, 7th April, 2025: Feature blogs ready for review
• You can find more in the release document

Note

In your placeholder PR, use XX characters for the blog date in the front matter and file name. We will work with you on updating the PR with the publication date once we have a final number of feature blogs for this release.

[Udi-Hofesh]

Hi @jingczhang 👋, 1.33 Communications Team here again!

This is a gentle reminder for the feature blog deadline mentioned above, which is 02:00 UTC Wednesday, 5th March, 2025. To opt in, please let us know and open a Feature Blog placeholder PR against k/website by the deadline. If you have any questions, please feel free to reach out to us!

Tip

Some timeline to keep in mind:

• 02:00 UTC Wednesday, 5th March, 2025: Feature blog PR freeze
• Monday, 7th April, 2025: Feature blogs ready for review
• You can find more in the release document

Note

In your placeholder PR, use XX characters for the blog date in the front matter and file name. We will work with you on updating the PR with the publication date once we have a final number of feature blogs for this release.

[jingczhang]

Hi @Udi-Hofesh, we will simply move the KEP to beta in 1.33, we will not write a new blog. Thank you.

[Udi-Hofesh]

Fair enough @jingczhang :) thank you!

[dipesh-rawat]

Hi @jingczhang 👋, v1.33 Enhancements team here,

Just a quick friendly reminder as we approach the code freeze later this week, at 02:00 UTC Friday 21st March 2025 / 19:00 PDT Thursday 20th March 2025.

The current status of this enhancement is marked as At risk for code freeze. There are a few requirements mentioned in the comment #4540 (comment) that still need to be completed.

If you anticipate missing code freeze, you can file an exception request in advance. Thank you!

[ffromani]

/reopen

[k8s-ci-robot]

@ffromani: Reopened this issue.

In response to this:

/reopen

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[dipesh-rawat]

Hey @jingczhang 👋, 1.33 Enhancements team here,

With all the implementation(code related) PRs merged as per the issue description:

• KEP-4540: strict-cpu-reservation beta kubernetes#130290

This enhancement is now marked as tracked for code freeze for the 1.33 Code Freeze!

Additionally, please let me know if there are any other PRs in k/k not listed in the description that we should track for this KEP, so that we can maintain accurate status.

[jingczhang]

Hi @dipesh-rawat, we are all done for 1.33. Thank you.