- HPA controller exposes the following metrics from the kube-controller-manager. 
  - `metric_computation_duration_seconds`: The time(seconds) that the HPA controller takes to calculate one metric.

- Registered_metric_total, disabled_metric_total, hidden_metric_total & kubernetes_feature_enabled are promoted to `BETA` stability. ([#119264](https://github.com/kubernetes/kubernetes/pull/119264), [@logicalhan](https://github.com/logicalhan)) [SIG API Machinery, Architecture, Cluster Lifecycle...

`autoscaling/v2alpha1`. The Horizontal Pod Autoscaler changes include support for status conditions, and autoscaling on memory and custom metrics.

* The metrics APIs, `custom-metrics.metrics.k8s.io` and `metrics`, were moved from `v1alpha1` to `v1beta1`, and renamed to `custom.metrics.k8s.io` and `metrics.k8s.io`, respectively. If you have deployed a custom metrics adapter, ensure that it supports the new API version. If you have deployed Heapster in aggregated API server mode, upgrade Heapster...

- A new kubelet metric `image_pull_duration_seconds` was added. The metric tracks the duration (in seconds) it takes for an image to be pulled, including the time spent in the waiting queue of image puller. The metric is broken down by bucketed image size. ([#121719](https://github.com/kubernetes/kubernetes/pull/121719), [@ruiwen-zhao](https://github.com/ruiwen-zhao))

- 'Promoted `cronjob_job_creation_skew` metric to stable to follow the cronjob v2 controller,
  the following metrics had their name updated to match metrics API guidelines:
    - `cronjob_job_creation_skew_duration_seconds` -> `job_creation_skew_duration_seconds`.' ([#113008](https://github.com/kubernetes/kubernetes/pull/113008), [@soltysh](https://github.com/soltysh))

- Introduced new apiserver metric `apiserver_flowcontrol_current_inqueue_seats`. This metric is analogous to `apiserver_flowcontrol_current_inqueue_requests`, but tracks the total number of seats, as each request can take more than one seat. ([#119385](https://github.com/kubernetes/kubernetes/pull/119385), [@andrewsykim](https://github.com/andrewsykim))