- Flag `--concurrent-node-syncs` has been added to cloud node controller which defines how many workers in parallel will be initialising and synchronising nodes. ([#113104](https://github.com/kubernetes/kubernetes/pull/113104), [@pawbana](https://github.com/pawbana)) [SIG API Machinery, Cloud Provider and Scalability]

<p>
A complete program is created by linking a single, unimported package
called the <i>main package</i> with all the packages it imports, transitively.
The main package must
have package name <code>main</code> and
declare a function <code>main</code> that takes no
arguments and returns no value.
</p>

<pre>
func main() { … }
</pre>

<p>

`meta.k8s.io/v1beta1` and configurations must be changed to use the new API.  Clients may request alternate representations of normal Kubernetes objects by passing an `Accept` header like `application/json;as=Table;g=meta.k8s.io;v=v1beta1` or `application/json;as=PartialObjectMetadata;g=meta.k8s.io;v1=v1beta1`.  Older servers will ignore this representation or return an error if it is not available.  Clients may request fallback to the normal object by adding a non-qualified mime-type to their `Accept`...

- Authentication token cache size is increased (from 4k to 32k) to support clusters with many nodes or many namespaces with active service accounts. ([#83643](https://github.com/kubernetes/kubernetes/pull/83643), [@lavalamp](https://github.com/lavalamp))

  Now, when unschedulable Pods are updated, the scheduling queue checks with QueueingHint(s) whether the update may make the pods schedulable, and requeues them to activeQ/backoffQ **only when** at least one QueueingHint(s) return Queue. 
  

- Added a new scheduler metric, `pod_scheduling_sli_duration_seconds`,...

- Fixed a bug where init containers may fail to start due to a temporary container runtime failure. ([#127213](https://github.com/kubernetes/kubernetes/pull/127213), [@SergeyKanzhelev](https://github.com/SergeyKanzhelev)) [SIG Node]

- Revised `OpenAPI v2` fetching for CustomResourceDefinitions. CRDs are now aggregated lazily,
  which improves resource usage during installation of many CRDs. As a result, the first request
  to fetch the OpenAPI may be slower. ([#118808](https://github.com/kubernetes/kubernetes/pull/118808), [@Jefftree](https://github.com/Jefftree))

* Do not detach volume if mount in progress ([#71145](https://github.com/kubernetes/kubernetes/pull/71145), [@gnufied](https://github.com/gnufied))
* Improve efficiency of preemption logic in clusters with many pending pods. ([#72895](https://github.com/kubernetes/kubernetes/pull/72895), [@bsalamat](https://github.com/bsalamat))

  - `--port`
  - `--address`
  The insecure port flags `--port` may only be set to 0 now.
- Kube-scheduler: the `--port` and `--address` flags have no effect and would be removed in v1.24.
  The insecure port flags `--port` may only be set to 0 now.