### Other notable changes

* Fix creation of custom resources when the CRD contains non-conventional pluralization and subresources ([#66249](https://github.com/kubernetes/kubernetes/pull/66249), [@deads2k](https://github.com/deads2k))

* fix azure disk create failure due to sdk upgrade ([#67236](https://github.com/kubernetes/kubernetes/pull/67236), [@andyzhangx](https://github.com/andyzhangx))
* Fix creation of custom resources when the CRD contains non-conventional pluralization and subresources ([#66249](https://github.com/kubernetes/kubernetes/pull/66249), [@deads2k](https://github.com/deads2k))

- Fix creation of custom resources when the CRD contains non-conventional pluralization and subresources ([#66249](https://github.com/kubernetes/kubernetes/pull/66249), [@deads2k](https://github.com/deads2k))

<h2 id="Errors">Errors</h2>

<p>
The predeclared type <code>error</code> is defined as
</p>

<pre>
type error interface {
	Error() string
}
</pre>

<p>
It is the conventional interface for representing an error condition,
with the nil value representing no error.
For instance, a function to read data from a file might be defined:
</p>

<pre>

  - If the custom resource participates the spec/status convention, the metadata.generation of the CR increments when there is any change, except for the changes to the metadata or the changes to the status.
  - If the custom resource does not participate the spec/status convention, the metadata.generation of the CR increments when there is any change to the CR, except for changes to the metadata.

* genericapiserver: unify swagger and openapi in config ([#38690](https://github.com/kubernetes/kubernetes/pull/38690), [@sttts](https://github.com/sttts))

### Client
* Use Prometheus instrumentation conventions ([#36704](https://github.com/kubernetes/kubernetes/pull/36704), [@fabxc](https://github.com/fabxc))

* kube-apiserver: improves performance of requests made with service account token authentication ([#71816](https://github.com/kubernetes/kubernetes/pull/71816), [@liggitt](https://github.com/liggitt))
* Use prometheus conventions for workqueue metrics. ([#71300](https://github.com/kubernetes/kubernetes/pull/71300), [@danielqsj](https://github.com/danielqsj))
    * It is now deprecated to use the following metrics:
        * `{WorkQueueName}_depth`

  -  Remove already deprecated options `resyncperiod` and `upstream` in the Kubernetes plugin.
  -  Includes Prometheus metrics name changes (to bring them in line with standard Prometheus metrics naming convention). They will be backward incompatible with existing reporting formulas that use the old metrics' names.
  -  The federation plugin (allows for v1 Kubernetes federation) has been removed.

* custom resources that use unconventional pluralization now work properly with kubectl and garbage collection ([#50012](https://github.com/kubernetes/kubernetes/pull/50012), [@deads2k](https://github.com/deads2k))

* Ignore pods marked for deletion that exceed their grace period in ResourceQuota ([#46542](https://github.com/kubernetes/kubernetes/pull/46542), [@derekwaynecarr](https://github.com/derekwaynecarr))
* custom resources that use unconventional pluralization now work properly with kubectl and garbage collection ([#50012](https://github.com/kubernetes/kubernetes/pull/50012), [@deads2k](https://github.com/deads2k))