KEP-4540: Add CPUManager policy option to restrict reservedSystemCPUs to system daemons and interrupt processing #4540

[jingczhang]

• One-line PR description: Adding new KEP
• Issue link: https://github.com/kubernetes/enhancements/issues/4540
• Code PR link: https://github.com/kubernetes/kubernetes/pull/123979
• HTML quick link: https://github.com/nokia/kubernetes-enhancements/tree/4540-strict-cpu-reservation/keps/sig-node/4540-strict-cpu-reservation

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[k8s-ci-robot]

Hi @jingczhang. Thanks for your PR.

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[jingczhang]

Initial PR to get reviewers agreement and guidance. Detailed design will be populated after that.

[bart0sh]

/ok-to-test /cc @ffromani @swatisehgal

[jingczhang]

Completed the KEP writing. Created the initial kubelet PR to get reviewers comments and guidance. More test cases will be added.

[swatisehgal]

Please run make update-toc to ensure that the Table of Contents is updated based on the content of the enhancement.

[jingczhang]

Updated "RIsks and Mitigations" section for impact on reduced shared pool size. Please review and advise.

[ffromani]

/remove-sig apps /remove-sig autoscaling /remove-sig scheduling /remove-sig auth

[jingczhang]

I updated the KEP to catch up the discussion on feature risk to make it easier for further review. Please check and advise.

[jingczhang]

/add-sig scheduling

[ffromani]

/sig scheduling

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: jingczhang Once this PR has been reviewed and has the lgtm label, please assign derekwaynecarr for approval. For more information see the Kubernetes Code Review Process.

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[jingczhang]

@swatisehgal @ffromani I have updated KEP and supporting code to support MinSharedCPUs in Kubelet and 'exclusive-cpu' in NodeAllocatable. Please review and confirm we are aligned. Scheduler change will be added soon.