- Fixed a scheduler preemption issue where the victim pod was not deleted due to incorrect status patching. This issue occurred when the preemptor and victim pods had different QoS classes in their status, causing the preemption to fail entirely. ([#126644](https://github.com/kubernetes/kubernetes/pull/126644), [@Huang-Wei](https://github.com/Huang-Wei))

- Fixed a suboptimal scheduler preemption behavior where potential preemption victims were violating Pod Disruption Budgets. ([#128435](https://github.com/kubernetes/kubernetes/pull/128435), [@NoicFank](https://github.com/NoicFank)) [SIG Scheduling]

## Dependencies

### Added

- Fixed a 1.26 regression scheduling bug by ensuring that preemption is skipped when a PreFilter plugin returns `UnschedulableAndUnresolvable` ([#119952](https://github.com/kubernetes/kubernetes/pull/119952), [@sanposhiho](https://github.com/sanposhiho)) [SIG Scheduling]

* **[Pod priority and preemption](https://kubernetes.io/docs/concepts/configuration/pod-priority-preemption/) is now enabled by default.** Note that this means that pods from *any* namespace can now request priority classes that compete with and/or cause preemption of critical system pods that are already running. If that is not desired, disable the PodPriority feature by setting `--feature-...

- Fixed a suboptimal scheduler preemption behavior where potential preemption victims were violating Pod Disruption Budgets. ([#128434](https://github.com/kubernetes/kubernetes/pull/128434), [@NoicFank](https://github.com/NoicFank)) [SIG Scheduling]

## Dependencies

### Added

Pod Priority and Preemption in Kubernetes ([#564](https://github.com/kubernetes/enhancements/issues/564))

creation of PriorityClasses ([user doc](https://kubernetes.io/docs/concepts/configuration/pod-priority-preemption/))([design doc](https://github.com/kubernetes/community/blob/master/contributors/design-proposals/scheduling/pod-priority-api.md))

* [alpha] This version now supports priority-based preemption of pods ([user doc](https://kubernetes.io/docs/concepts/configuration/pod-priority-preemption/))([design doc](https://github.com/kubernetes/community/blob/master/contributors/design-propos...

- Migrate  `pkg/kubelet/pluginmanager`  to structured logging ([#99885](https://github.com/kubernetes/kubernetes/pull/99885), [@qingwave](https://github.com/qingwave)) [SIG Node]
- Migrate  `pkg/kubelet/preemption/preemption.go` and `pkg/kubelet/logs/container_log_manager.go` to structured logging ([#99848](https://github.com/kubernetes/kubernetes/pull/99848), [@qingwave](https://github.com/qingwave)) [SIG Node]

- Fixed a bug that the async preemption feature keeps preemptor pods unnecessarily in the queue. ([#133167](https://github.com/kubernetes/kubernetes/pull/133167), [@sanposhiho](https://github.com/sanposhiho)) [SIG Scheduling]

* Allow for watching objects larger than 1MB given etcd accepts objects of size up to 1.5MB ([#72053](https://github.com/kubernetes/kubernetes/pull/72053), [@wojtek-t](https://github.com/wojtek-t))
* Improve efficiency of preemption logic in clusters with many pending pods. ([#72895](https://github.com/kubernetes/kubernetes/pull/72895), [@bsalamat](https://github.com/bsalamat))



# v1.12.5

[Documentation](https://docs.k8s.io)