* Returns an iterator over the merged contents of all given {@code iterators}, traversing every
   * element of the input iterators. Equivalent entries will not be de-duplicated.
   *
   * <p>Callers must ensure that the source {@code iterators} are in non-descending order as this
   * method does not sort its input.
   *
   * <p>For any equivalent elements across all {@code iterators}, elements are returned in the order

### OpenStack

* The NamespaceExists and NamespaceAutoProvision admission controllers have been removed. ([#31250](https://github.com/kubernetes/kubernetes/pull/31250), [@derekwaynecarr](https://github.com/derekwaynecarr))
    * All cluster operators should use NamespaceLifecycle.

on average) and rapid updates to pod configuration should take effect sooner.
  
  A new metric `kubelet_known_pods` has been added at ALPHA stability to report the number of pods a Kubelet is tracking in a number of internal states.  Operators may use the metrics to track an excess of pods in the orphaned state that may not be completing. ([#113145](https://github.com/kubernetes/kubernetes/pull/113145), [@smarterclayton](https://github.com/smarterclayton)) [SIG API Machinery, Auth, Cloud...

* The NamespaceExists and NamespaceAutoProvision admission controllers have been removed. ([#31250](https://github.com/kubernetes/kubernetes/pull/31250), [@derekwaynecarr](https://github.com/derekwaynecarr))
    * All cluster operators should use NamespaceLifecycle.

    * of DaemonSet Pod already exists, it will be replaced.
    * DaemonSet controller will only perform these operations when creating DaemonSet Pods;
    * and those operations will only modify the Pods of DaemonSet, no changes are made to the
    * `.spec.template` of DaemonSet.

- [Namespaced Brokers](https://svc-cat.io/docs/namespaced-broker-resources/), which enable operators to install a broker into a namespace instead of the cluster level, reached GA.
- The [Service Plan Defaults](https://svc-cat.io/docs/service-plan-defaults/) feature is in alpha and is under active development. This feature gives operators the ability to define defaults for when someone provisions a service.

     `CSIMigrationRBD`: true

  As a Kubernetes cluster operator that administers storage, here are the prerequisites that you must complete before you attempt migration to the RBD CSI driver:

  * You must install the Ceph CSI driver (rbd.csi.ceph.com), v3.5.0 or above, into your Kubernetes cluster.

 * variety of sequences of the {@link Iterator#next}, {@link Iterator#hasNext} and {@link
 * Iterator#remove} operations. This utility takes the brute-force approach of trying <i>all</i>
 * possible sequences of these operations, up to a given number of steps. So, if the caller
 * specifies to use <i>n</i> steps, a total of <i>3^n</i> tests are actually performed.
 *

 * while adding a new pair.
 *
 * <p>This class is not threadsafe when any concurrent operations update the multimap, even if the
 * underlying map and {@link #createCollection()} method return threadsafe classes. Concurrent read
 * operations will work correctly. To allow concurrent update operations, wrap your multimap with a
 * call to {@link Multimaps#synchronizedMultimap}.
 *