HPA: Improve pod selection accuracy across workload types

[omerap12]

Enhancement Description

HPA may include metrics from unrelated pods if they share the same labels as the target workload. This can cause incorrect scaling, such as staying at maxReplicas even when real usage is low. This proposal updates the HPA to only use pods directly managed by the target workload, avoiding incorrect metrics and improving scaling accuracy.

• One-line enhancement description (can be used as a release note): Improve HPA pod selection accuracy across workload types
• Kubernetes Enhancement Proposal: [in progress]
• Discussion Link:
  • 20 May 2025 SIG Autoscaling meeting
  • HPA stuck at maxReplicas even though metric under target kubernetes#120875 (comment)
• Primary contact (assignee): @omerap12, @adrianmoisey
• Responsible SIGs: SIG Autoscaling
• Enhancement target (which target equals to which milestone):
  • Alpha release target (x.y): 1.34
  • Beta release target (x.y):
  • Stable release target (x.y):
• Alpha
  • KEP (k/enhancements) update PR(s): KEP-5325: HPA - Improve pod selection accuracy across workload types #5331
  • Code (k/k) update PR(s): [WIP] HPA - pod selection strategy kubernetes#132018
  • Docs (k/website) update PR(s):

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

[omerap12]

/sig autoscaling

[gjtempleton]

/label lead-opted-in
/milestone v1.34

[jenshu]

Hi @omerap12 @adrianmoisey 👋, v1.34 Enhancements team here.

This is a reminder of the upcoming PRR Freeze on Thursday 12th June 2025.

By this date, there must be a PR open in k/enhancements with:

• The KEP's PRR questionnaire filled out.
• The kep.yaml updated with the stage, latest-milestone, and milestone struct filled out.
• A PRR approval file with the PRR approver listed for the stage the KEP is targeting.

Having the PRR questionnaire filled out by this deadline will help ensure that the PRR team has enough time to review your KEP before Enhancements Freeze on Friday 20th June 2025. For more information on the PRR process, see here.

[jenshu]

Hello again @omerap12 @adrianmoisey 👋, v1.34 Enhancements team here.

Just checking in as we approach enhancements freeze on 21:00 UTC Friday 20th June 2025 / 14:00 PST Friday 20th June 2025.

This enhancement is targeting stage alpha for v1.34 (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: v1.34.
• 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 12th June 2025 so that the PRR team has enough time to review your KEP.

I see that you have a PR open with these changes.

• In the kep.yaml, can you also update the status to implementable?

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!