container, and uses `oom_scores` to recommend an order for killing container processes if an out-of-memory event occurs. This implementation has shortcomings: for `Guaranteed` pods, memory can not be fully reserved, and the page cache is at risk of being recycled. For `Burstable` pods, overcommitting memory (setting `request` less than `limit` ) could increase the risk of a container being killed when the Linux kernel detects an out of memory condition.

As an alpha feature, Kubernetes v1.22 can...

* 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))

- Fixed a bug where pv recycler failed to scrub volume with too many files in the directory due to hitting ARG_MAX limit with rm command (#117189). ([#117283](https://github.com/kubernetes/kubernetes/pull/117283), [@defo89](https://github.com/defo89)) [SIG Cloud Provider and Storage]...

#### Extensibility

- The community has been asking for continuing support of extensibility, so this cycle features more work around CRDs and API Machinery. Most of the enhancements in this cycle were from SIG API Machinery and related areas.

### Extensibility around core Kubernetes APIs

#### CustomResourceDefinitions Pruning

    * a. kubectl get pod test-pod -o custom-columns=CONTAINER:.spec.containers[0:3].name
    * b. kubectl get pod test-pod -o custom-columns=CONTAINER:.spec.containers[-2:].name
* 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))

    * request a client certificate from the API server during the boot cycle and pause
    * waiting for the request to be satisfied. It will continually refresh the certificate
    * as the certificates expiration approaches.

- Scheduler framework permit plugins now run at the end of the scheduling cycle, after reserve plugins. Waiting on permit will remain in the beginning of the binding cycle. ([#88199](https://github.com/kubernetes/kubernetes/pull/88199), [@mateuszlitwin](https://github.com/mateuszlitwin)) [SIG Scheduling]

- When using `kubectl replace` (or the equivalent API call) on a Service, the caller no longer needs to do a read-modify-write cycle to fetch the allocated values for `.spec.clusterIP` and `.spec.ports[].nodePort`.  Instead the API server will automatically carry these forward from the original object when the new object does not specify them. ([#104673](https://github.com/kube...

2670..2671    ; valid                  ;      ; NV8    # 3.0  WEST SYRIAC CROSS..EAST SYRIAC CROSS
2672..267D    ; valid                  ;      ; NV8    # 3.2  UNIVERSAL RECYCLING SYMBOL..PARTIALLY-RECYCLED PAPER SYMBOL
267E..267F    ; valid                  ;      ; NV8    # 4.1  PERMANENT PAPER SIGN..WHEELCHAIR SYMBOL
2680..2689    ; valid                  ;      ; NV8    # 3.2  DIE FACE-1..BLACK CIRCLE WITH TWO WHITE DOTS

- When using `kubectl replace` (or the equivalent API call) on a Service, the caller no longer needs to do a read-modify-write cycle to fetch the allocated values for `.spec.clusterIP` and `.spec.ports[].nodePort`.  Instead the API server will automatically carry these forward from the original object when the new object does not specify them. ([#104674](https://github.com/kube...