- Improved scheduling performance when many nodes, and prefilter returns 1-2 nodes (e.g. daemonset)
  

### API Change

- **ACTION REQUIRED** for custom scheduler plugin developers:
  `PodEligibleToPreemptOthers` in the `preemption` interface now includes `ctx` in the parameters.

  
  Action required for custom scheduler plugin developers:
  Plugins **have to** implement a QueueingHint for Pod/Update event if the rejection from them could be resolved by updating unscheduled Pods themselves.

      * Added exported env vars to kubectl plugins so that plugin developers have access to global flags, namespace, the plugin descriptor and the full path to the caller binary.

  * Enhancement

 - Scheduler's CycleState now embeds internal read/write locking inside its `Read()` and `Write()` functions. Meanwhile, `Lock()` and `Unlock()` function are removed. Scheduler plugin developers are now required to remove `CycleState#Lock()` and `CycleState#Unlock()`. Just simply use `Read()` and `Write()` as they're natively thread-safe now. ([#101542](https://github.com/kubernetes/kubernetes/pull/101542), [@Huang-Wei](https://github.com/Huang-Wei))...

containers](https://kubernetes.io/docs/concepts/workloads/pods/ephemeral-containers/), it became more obvious how we can support developers with tooling built on top of `kubectl exec`. The addition of the `kubectl debug` [command](https://github.com/kubernetes/enhancements/blob/master/keps/sig-cli/1441-kubectl-debug/README.md) (it is alpha but your feedback is more than welcome), allows developers to easily debug their Pods inside the cluster. We think this addition is invaluable.  This command allows one to create...

 - Renamed `UpdatePodTolerations` action type to `UpdatePodToleration`.
  Action required for custom plugin developers to update their code to follow the rename. ([#129023](https://github.com/kubernetes/kubernetes/pull/129023), [@zhifei92](https://github.com/zhifei92)) [SIG Scheduling and Testing]
 
## Changes by Kind

### Deprecation

## Changelog since v1.28.10

## Changes by Kind

### API Change

- Improved scheduling performance when many nodes, and prefilter returns 1-2 nodes (e.g. daemonset)
  

- For scheduler plugin developers: the scheduler framework's shared PodInformer is now initialized with empty indexers. This enables scheduler plugins to add their extra indexers. Note that only non-conflict indexers are allowed to be added. ([#110663](https://github.com/kubern...

With CSI the Kubernetes volume layer becomes truly extensible, allowing third party storage developers to write drivers making their storage systems available in Kubernetes without having to touch the core code.

CSI was first introduction as alpha in Kubernetes v1.9 and moved to beta in Kubernetes v1.10.