*   AWS EBS volumes are detached if attached to a different node than expected. ([#55491](https://github.com/kubernetes/kubernetes/pull/55491),[ @gnufied](https://github.com/gnufied))
    *   PV Recycle now works in environments that use architectures other than x86. ([#53958](https://github.com/kubernetes/kubernetes/pull/53958),[ @dixudx](https://github.com/dixudx))

  // Valid options are Retain (default for manually created PersistentVolumes), Delete (default
  // for dynamically provisioned PersistentVolumes), and Recycle (deprecated).
  // Recycle must be supported by the volume plugin underlying this PersistentVolume.
  // More info: https://kubernetes.io/docs/concepts/storage/persistent-volumes#reclaiming
  // +optional

     * -Djcifs.smb1.smb.client.soTimeout=35000<br>
     * -Djcifs.smb1.smb.client.responseTimeout=30000<br>
     * -Dio.netty.noUnsafe=true<br>
     * -Dio.netty.noKeySetOptimization=true<br>
     * -Dio.netty.recycler.maxCapacityPerThread=0<br>
     * -Dlog4j.shutdownHookEnabled=false<br>
     * -Dlog4j2.formatMsgNoLookups=true<br>
     * -Dlog4j2.disable.jmx=true<br>
     * -Dlog4j.skipJansi=true<br>

* 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 potential infinite loop that can occur when NFS PVs are recycled. ([#62572](https://github.com/kubernetes/kubernetes/pull/62572), [@joelsmith](https://github.com/joelsmith))

- 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]...

- 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]

#### 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

* 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))

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...