- kube-controller-manager now uses the informer cache instead of active pod gets in HPA controller ([#68241](https://github.com/kubernetes/kubernetes/pull/68241), [@krzysztof-jastrzebski](https://github.com/krzysztof-jastrzebski))

The `IngressClass` resource is used to describe a type of Ingress within a Kubernetes cluster. Ingresses can specify the class they are associated with by using a new `ingressClassName` field on Ingresses. This new resource and field replace the deprecated `kubernetes.io/ingress.class` annotation.

### SIG CLI introduces kubectl debug

* Make all e2e tests lookup image to use from a centralized place. In that centralized place, add support for multiple platforms. ([#49457](https://github.com/kubernetes/kubernetes/pull/49457), [@mkumatag](https://github.com/mkumatag))

- When scaling down a ReplicaSet, delete doubled up replicas first, where a "doubled up replica" is defined as one that is on the same node as an active replica belonging to a related ReplicaSet.  ReplicaSets are considered "related" if they have a common controller (typically a Deployment). ([#80004](https://github.com/kubernetes/kubernetes/pull/80004), [@Miciah](https:/...

   APPENDIX: How to apply the Apache License to your work.

      To apply the Apache License to your work, attach the following
      boilerplate notice, with the fields enclosed by brackets "[]"
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   APPENDIX: How to apply the Apache License to your work.

      To apply the Apache License to your work, attach the following
      boilerplate notice, with the fields enclosed by brackets "[]"
      replaced with your own identifying information. (Don't include
      the brackets!)  The text should be enclosed in the appropriate
      comment syntax for the file format. We also recommend that a

  apiserver_flowcontrol_current_executing_requests ([#119110](https://github.com/kubernetes/kubernetes/pull/119110), [@andrewsykim](https://github.com/andrewsykim)) [SIG API Machinery and Instrumentation]
- Replace `apiserver_storage_db_total_size_in_bytes` with `apiserver_storage_size_bytes` metric ([#118812](https://github.com/kubernetes/kubernetes/pull/118812), [@serathius](https://github.com/serathius)) [SIG API Machinery, Instrumentation and Testing]

- Removed the following deprecated metrics:
  - node_collector_evictions_number replaced by node_collector_evictions_total
  - scheduler_e2e_scheduling_duration_seconds replaced by scheduler_scheduling_attempt_duration_seconds ([#115209](https://github.com/kubernetes/kubernetes/pull/115209), [@dgrisonnet](https://github.com/dgrisonnet))

### API Change

* Make all e2e tests lookup image to use from a centralized place. In that centralized place, add support for multiple platforms. ([#49457](https://github.com/kubernetes/kubernetes/pull/49457), [@mkumatag](https://github.com/mkumatag))