Support PSI based on cgroupv2

[ndixita]

Enhancement Description

• One-line enhancement description (can be used as a release note): Integrating PSI metrics in K8s and using those to set node conditions.
• Kubernetes Enhancement Proposal: https://github.com/kubernetes/enhancements/blob/master/keps/sig-node/4205-psi-metric/README.md
• Discussion Link:
• Primary contact (assignee): @ndixita
• Responsible SIGs: sig-node
• Enhancement target (which target equals to which milestone):
  • Alpha release target (x.y): 1.33
  • Beta release target (x.y):
  • Stable release target (x.y):
• Alpha
  • KEP (k/enhancements) update PR(s):
    • 1.29: KEP-4205: KEP to add PSI metrics in Summary API, and for PSI based node actions #4230
    • 1.30: KEP-4025: several formatting fixes #4360
    • 1.30: KEP-4205: updating the milestone for alpha to 1.30 #4454
    • 1.32: 4205: retarget to 1.32 #4883
    • 1.33: 4205: bump to 1.33 #5111 KEP-4205: Update PSI KEP for 1.33 #5155
  • Code (k/k) update PR(s):
    • 1.32 vendor: bump runc/libcontainer to v1.2.1 kubernetes#128276
    • Runc 1.2.0 libct/cg/stats: support PSI for cgroup v2 opencontainers/runc#3900
    • Containerd 2.0 only(not included in v1.7 containerd) support psi containerd/cgroups#308
    • Cadvisor: Add Pressure Stall Information Metrics google/cadvisor#3649
    • Surface Pressure Stall Information (PSI) metrics kubernetes#130701
  • Docs (k/website) update PR(s): KEP 4205: draft PR for PSI KEP website#48468
    • KEP-4205: update for alpha release in 1.33 website#49895

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

[pacoxu]

/sig node

[SergeyKanzhelev]

/milestone v1.29
/label lead-opted-in
/stage alpha

@ndixita please fill up more details in the issue description. Accepting as we discussed at SIG Node meeting this week

[tzneal]

/cc

[rayandas]

Hello @ndixita 👋, v1.29 Enhancements team here.

Just checking in as we approach enhancements freeze on 01:00 UTC, Friday, 6th October, 2023.

This enhancement is targeting for stage alpha for v1.29 (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: 1.29.
• KEP has a production readiness review that has been completed and merged into k/enhancements.

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

• The latest readme template has more items in production readiness review questionnaire that need to be addressed.
• The status should be marked as implementable in the kep.yaml file.
• Ensure that the PR including the production readiness review has been reviewed 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. Thank you!

[rayandas]

Hi @ndixita 👋🏽 checking in once more as we approach the 1.29 enhancement freeze deadline on 01:00 UTC, Friday, 6th October, 2023. The status of this enhancement is marked as at risk for enhancement freeze.
It looks like PR #4230 will address most of the requirements. Let me know if I missed anything. Thanks.

[ndixita]

The KEP PR is updated, and the comments are resolved. I am waiting for PRR review

[npolshakova]

With KEP PR #4230 approved, the enhancement is ready for the enhancements freeze. The status is now marked as tracked for enhancement freeze for 1.29. 🚀 Thank you!

[katcosgrove]

Hey there @ndixita! 👋, v1.29 Docs Lead here.
Does this enhancement work planned for v1.29 require any new docs or modification to existing docs?
If so, please follows the steps here to open a PR against dev-1.29 branch in the k/website repo. This PR can be just a placeholder at this time and must be created before Thursday, 19 October 2023.
Also, take a look at Documenting for a release to get yourself familiarize with the docs requirement for the release.
Thank you!

[katcosgrove]

Hi again @ndixita! The deadline to open a placeholder PR against k/website for required documentation is this Thursday, 19 October. Could you please update me on the status of docs for this enhancement? Thank you!

[rayandas]

Hey again @ndixita 👋, 1.29 Enhancements team here,

Just checking in as we approach code freeze at 01:00 UTC Wednesday 1st November 2023: .

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 PR/s are ready to be merged (they have approved and lgtm labels applied) by the code freeze deadline. This includes tests.

Please update the Issue description to include all the related PRs of this KEP under the stable section in the Github Issue description. The status for this KEP is currently at risk for code freeze.

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

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

[a-mccarthy]

Hi @ndixita, 👋 from the v1.29 Release Team-Communications! We would like to check if you have any plans to publish a blog for this KEP regarding new features, removals, and deprecations for this release.

If so, you need to open a PR placeholder in the website repository.
The deadline will be on Tuesday 14th November 2023 (after the Docs deadline PR ready for review)

Here is the 1.29 calendar

[ndixita]

@a-mccarthy This feature is postponed to 1.30 release

[npolshakova]

Hello @ndixita 👋 1.29 Enhancements lead here,

Unfortunately, the implementation (code related) PR(s) associated with this enhancement is not in the merge-ready state by code-freeze and hence this enhancement is now removed from the 1.29 milestone.

If you still wish to progress this enhancement in 1.29, please file an exception request. Thanks!

/milestone clear

[amannijhawan]

This would be quite useful to have as we can use the psi metrics as a good proxy for memory pressure and potential for OOMKILL.

Thanks
Aman

[jenshu]

Hello @ndixita @haircommander 👋, 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 alpha for v1.33 (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: v1.33.
• 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:

• in the kep.yaml, the latest-milestone should be set to v1.33 (I see you already have a PR open for it, so that just needs to merge)

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!

[kannon92]

@jenshu I have #5155 to address your last concern.

[jenshu]

@kannon92 thank you, everything looks good now, I will move it to tracked!

[Urvashi0109]

Hello @ndixita @haircommander 👋, v1.33 Docs Shadow 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!

[rexagod]

(FYI) Amending #4205 (comment) above, the google/cadvisor#3083 effort was superseded by google/cadvisor#3649 and has been merged.

[haircommander]

draft doc update: kubernetes/website#49895

[aibarbetta]

Hi @ndixita @haircommander 👋 -- this is Agustina (@aibarbetta) 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 which fall into (but 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 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.

[jenshu]

Hey again @ndixita 👋, 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.

Per the issue description, these are all of the implementation (code-related) PRs for 1.33:

• Add Pressure Stall Information Metrics google/cadvisor#3649

Please let me know (and keep the issue description updated) if there are any other PRs in k/k that we should track for this KEP, so that we can maintain accurate status.

This enhancement is now marked as Tracked for code freeze for the v1.33 Code Freeze!

[aibarbetta]

Hi @ndixita @haircommander 👋, 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.

[roycaihw]

cadvisor vendor update is done. k/k implementation is under review. Will also update k8s documentation.

[jenshu]

Hi @roycaihw @haircommander @ndixita since there is still a PR open (kubernetes/kubernetes#130701) I have moved this back to At risk for code freeze

[jenshu]

Hello @roycaihw @haircommander @ndixita 👋, v1.33 Enhancements team here,

Unfortunately, the implementation (code related) PR(s) associated with this enhancement are not in the merge-ready state by code-freeze and hence this enhancement is now removed from the v1.33 milestone.

If you still wish to progress this enhancement in v1.33, please file an exception request as soon as possible, within three days. If you have any questions, you can reach out in the #release-enhancements channel on Slack and we'll be happy to help. Thanks!

/milestone clear

[dipesh-rawat]

Hello @roycaihw @haircommander @ndixita 👋, v1.33 Enhancements team here,

The release team has APPROVED the exception request here, so this KEP can now be considered to be added back to the v1.33 milestone. The updated deadline to merge all related PRs is 11:00 PDT on Monday, 24th March 2025.

If you have any questions, feel free to reach out in the Exception Request thread of this KEP on Slack in the #sig-release channel - we’re happy to help. Also, once the code PRs are merged, please feel free to let us know here. Once the PRs are merged, the milestone will be re-added accordingly.
Thanks!

[dipesh-rawat]

Hey @roycaihw @haircommander @ndixita 👋, v1.33 Enhancements team here,

With implementation PR kubernetes/kubernetes#130701 merged. This enhancement is now marked as tracked for code freeze for the v1.33 release!

/milestone v1.33