For more information, see [#53288](https://issue.k8s.io/53288).

* `kubeadm init` and `kubeadm join` invocations on newly installed systems can encounter a `/var/lib/kubelet is not empty` message during pre-flight checks that prevents setup. If this is the only pre-flight failure, it can be safely ignored with `--skip-preflight-checks`.

For more information, see [#53356](https://issue.k8s.io/53356#issuecomment-333748618).

* scheduler: use incremental scheduling cycle in PriorityQueue to put all in-flight unschedulable pods back to active queue if we received move request ([#73309](https://github.com/kubernetes/kubernetes/pull/73309), [@cofyc](https://github.com/cofyc))

* scheduler: use incremental scheduling cycle in PriorityQueue to put all in-flight unschedulable pods back to active queue if we received move request ([#73309](https://github.com/kubernetes/kubernetes/pull/73309), [@cofyc](https://github.com/cofyc))

  After the connection closed(received GOAWAY), the client's other in-flight requests won't be affected, and the client will reconnect. 
  The flag min value is 0 (off), max is .02 (1/50 requests); .001 (1/1000) is a recommended starting point.

* add goroutine to move unschedulable pods to activeq if they are not retried for more than 1 minute ([#72558](https://github.com/kubernetes/kubernetes/pull/72558), [@denkensk](https://github.com/denkensk))
* Scale max-inflight limits together with master VM sizes. ([#73268](https://github.com/kubernetes/kubernetes/pull/73268), [@wojtek-t](https://github.com/wojtek-t))

- Kube-proxy service health returns http header `X-Load-Balancing-Endpoint-Weight` with number of local endpoints. The same information is still available in response body JSON `payload.LocalEndpoints`. ([#118999](https://github.com/kubernetes/kubernetes/pull/118999), [@cezarygerard](https://github.com/cezarygerard))

 - CSINode initialization does not crash kubelet on startup when APIServer is not reachable or kubelet has not the right credentials yet. ([#89589](https://github.com/kubernetes/kubernetes/pull/89589), [@jsafrane](https://github.com/jsafrane)) [SIG Storage]

* Add apiserver metric for number of requests dropped because of inflight limit. ([#58340](https://github.com/kubernetes/kubernetes/pull/58340), [@gmarek](https://github.com/gmarek))
* Add apiserver metric for current inflight-request usage. ([#58342](https://github.com/kubernetes/kubernetes/pull/58342), [@gmarek](https://github.com/gmarek))

- Overall, enable the feature of `PreferNominatedNode` will  improve the performance of scheduling where preemption might frequently happen, but in theory, enable the feature of `PreferNominatedNode`, the pod might not be scheduled to the best candidate node in the cluster. ([#93179](https://github.com/kubernetes/kubernetes/pull/93179), [@chendave](https://github.com/chendave)) [SIG Scheduling and Testing]

* Enable prometheus apiserver metrics for custom resources. ([#57682](https://github.com/kubernetes/kubernetes/pull/57682), [@nikhita](https://github.com/nikhita))

* Add apiserver metric for number of requests dropped because of inflight limit, making it easier to figure out on which dimension the master is overloaded. ([#58340](https://github.com/kubernetes/kubernetes/pull/58340), [@gmarek](https://github.com/gmarek))