- Scheduler doesn't run plugin's Filter method when its PreFilter method returned a Skip status.
  In other words, your PreFilter/Filter plugin can return a Skip status in PreFilter if the plugin does nothing in Filter for that Pod.
  Scheduler skips NodeAffinity Filter plugin when NodeAffinity Filter plugin has nothing to do with a Pod.

conjunction with SIG Cloud Provider, is focusing on moving internal APIs that the OpenStack (and other providers) depends upon to staging to guarantee API stability. This work also included abstracting the in-tree Cinder API and refactoring code to the external Cinder provider to remove additional Cinder volume provider code.

Additional work was also done to implement an OpenStack driver for the Cluster API effort lead by SIG Cluster Lifecycle. For the external Cloud-Provider-OpenStack code, the...

- OpenStack Cinder CSI migration is now GA and switched on by default, Cinder CSI driver must be installed on clusters on OpenStack for Cinder volumes to work (has been since v1.21). ([#107462](https://github.com/kubernetes/kubernetes/pull/107462), [@dims](https://github.com/dims))

- [migration phase 1] PodFitsHostPorts as filter plugin ([#83659](https://github.com/kubernetes/kubernetes/pull/83659), [@wgliang](https://github.com/wgliang))
- [migration phase 1] PodFitsResources as framework plugin ([#83650](https://github.com/kubernetes/kubernetes/pull/83650), [@wgliang](https://github.com/wgliang))

- The scheduler skips the `PodTopologySpread` Filter plugin if no spread constraints.
  It will affect some metrics values related to the `PodTopologySpread` Filter plugin. ([#117683](https://github.com/kubernetes/kubernetes/pull/117683), [@utam0k](https://github.com/utam0k))

    - All resources under `apps/v1beta1` and `apps/v1beta2` - use `apps/v1` instead
    - `daemonsets`, `deployments`, `replicasets` resources under `extensions/v1beta1` - use `apps/v1` instead
    - `networkpolicies` resources under `extensions/v1beta1` - use `networking.k8s.io/v1` instead
    - `podsecuritypolicies` resources under `extensions/v1beta1` - use `policy/v1beta1` instead

* PVC may not be synced to controller local cache in time if PV is bound by external PV binder (e.g. kube-scheduler), double check if PVC is not found to prevent reclaiming PV wrongly. ([#67062](https://github.com/kubernetes/kubernetes/pull/67062), [@cofyc](https://github.com/cofyc))

- Fix a regression that the scheduler always goes through all Filter plugins. ([#114524](https://github.com/kubernetes/kubernetes/pull/114524), [@Huang-Wei](https://github.com/Huang-Wei)) [SIG Scheduling]

### Feature

- A new metric `apiserver_request_filter_duration_seconds` has been introduced that 
  measures request filter latency in seconds. ([#95207](https://github.com/kubernetes/kubernetes/pull/95207), [@tkashem](https://github.com/tkashem)) [SIG API Machinery and Instrumentation]

  * You can find out what taints you have in place on a node while you are still running Kubernetes 1.5 by doing `kubectl describe node <node name>`; the `Taints` section will show the taints you have in place. To see the taints that were created under 1.5 when you are running 1.6, do `kubectl get node <node name> -o yaml` and look for the "Annotation" section with the annotation...