- The `DeclarativeValidation` feature gate is enabled by default. When enabled, mismatches with existing hand written validation is reported via metrics.

 - Log messages in JSON format are written to stderr by default now (same as text format) instead of stdout. Users who expected JSON output on stdout must now capture stderr instead or in addition to stdout. ([#106146](https://github.com/kubernetes/kubernetes/pull/106146), [@pohly](https:...

- The PodDisruptionBudget API has been promoted to policy/v1 with no schema changes. The only functional change is that an empty selector (`{}`) written to a policy/v1 PodDisruptionBudget now selects all pods in the namespace. The behavior of the policy/v1beta1 API remains unchanged. The policy/v1beta1 PodDisruptionBudget API is deprecated and will no longer be served in 1.25+. ([#99290](https://...

            }
        });

    }

    /**
     * Flushes the specified indices to ensure data is written to disk.
     *
     * @param indices the indices to flush
     */
    public void flush(final String... indices) {

  * For all other existing controllers except StatefulSet, this has no effect on
    the ability of the controller to replace pods because the controllers do not
    reuse pod names (they use generate-name).
  * User-written controllers that reuse names of pod objects should evaluate this change.
  * When deleting an object with `kubectl delete ... --grace-period=0`, the client will

*.spectrum.myjino.ru
*.statics.cloud
*.stg-builder.code.com
*.stg.dev
*.stgstage.dev
*.stolos.io
*.svc.firenet.ch
*.sys.qcx.io
*.telebit.xyz
*.transurl.be
*.transurl.eu
*.transurl.nl
*.triton.zone
*.tst.site
*.uberspace.de
*.upsun.app
*.us-east-1.airflow.amazonaws.com
*.us-east-2.airflow.amazonaws.com
*.us-west-1.airflow.amazonaws.com
*.us-west-2.airflow.amazonaws.com
*.user.fm

* RBAC objects are now stored in etcd in v1 format. After completing an upgrade to 1.9, RBAC objects (Roles, RoleBindings, ClusterRoles, ClusterRoleBindings) should be migrated to ensure all persisted objects are written in `v1` format, prior to `v1alpha1` support being removed in a future release. ([#52950](https://github.com/kubernetes/kubernetes/pull/52950), [@liggitt](https://github.com/liggitt))

### Other notable changes

- kubeadm: make sure the extra environment variables written to a kubeadm managed PodSpec are sorted alpha-numerically by the environment variable name. ([#126743](https://github.com/kubernetes/kubernetes/pull/126743), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]

users must manually remove this flag from their `kubelet` configuration to prevent startup failures before upgrading `kubelet`. For `kubeadm` clusters, if users pass extra arguments to the `kubelet` like `--pod-infra-container-image`, it will be written to the `kubelet` env file during the `init` phase. `kubeadm` does not remove it during the `init` or `join` phase, so users must manually remove it from `extraArgs` in the `kubelet` configuration file. ([#133779](https://github.com/kubernetes/kub...

      if (map.recordsAccess()) {
        entry.setAccessTime(now);
      }
      accessQueue.add(entry);
    }

    /**
     * Updates eviction metadata that {@code entry} was just written. This currently amounts to
     * adding {@code entry} to relevant eviction lists.
     */
    @GuardedBy("this")
    void recordWrite(ReferenceEntry<K, V> entry, int weight, long now) {