KEPs or supporting documentation, please reference a specific commit and avoid
  linking directly to the master branch. This ensures that links reference a
  specific point in time, rather than a document that may change over time.
  
  See here for guidance on getting permanent links to files: https://help.github.com/en/articles/getting-permanent-links-to-files
  
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focused on stability and performance improvements in the 1.13 release.  A new alpha feature is introduced to improve the mechanism that nodes heartbeat back to the control plane.  The `NodeLease` feature results in the node using a `Lease` resource in the `kube-node-lease` namespace that is renewed periodically.  The `NodeStatus` that was used previously to heartbeat back to the control plane is only updated when it changes.  This reduces load on the control plane for large clusters. The Kubelet plugin...

#### kubelet:
- `--enable-cadvisor-json-endpoints` is now disabled by default. If you need access to the cAdvisor v1 Json API please enable it explicitly in the kubelet command line. Please note that this flag was deprecated in 1.15 and will be removed in 1.19. ([#87440](https://github.com/kubernetes/kubernetes/pull/87440), [@dims](https://github.com/dims)) [SIG Instrumentation, Node and Testing]

### Feature

- Add flag --lease-max-object-size and metric etcd_lease_object_counts for kube-apiserver to config and observe max objects attached to a single etcd lease. ([#97480](https://github.com/kubernetes/kubernetes/pull/97480), [@lingsamuel](https://github.com/lingsamuel)) [SIG API Machinery, Instrumentation and Scalability]

- Kube-apiserver now maintains a Lease object to identify itself: 
  - The feature is under feature gate `APIServerIdentity`. 
  - Two flags are added to kube-apiserver: `identity-lease-duration-seconds`, `identity-lease-renew-interval-seconds` ([#95533](https://github.com/kubernetes/kubernetes/pull/95533), [@roycaihw](https://github.com/roycaihw)) [SIG API Machinery]

  * deleteOptions.orphanDependents is going to be deprecated in 1.7. Please use deleteOptions.propagationPolicy instead.

### kubeadm

  KEPs or supporting documentation, please reference a specific commit and avoid
  linking directly to the master branch. This ensures that links reference a
  specific point in time, rather than a document that may change over time.
  
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* Updates Fluentd to 1.3.2 & added filter_parser  ([#71180](https://github.com/kubernetes/kubernetes/pull/71180), [@monotek](https://github.com/monotek))
* The leaderelection package allows the lease holder to release its lease when the calling context is cancelled. This allows ([#71490](https://github.com/kubernetes/kubernetes/pull/71490), [@smarterclayton](https://github.com/smarterclayton))

  - AzureDiskLimits
  - CinderLimits
  - EBSLimits
  - GCEPDLimits
  
  The NodeVolumeLimits plugin can handle the same functionality as the above plugins since the above volume types are migrated to CSI.
  Please remove those plugins and replace them with the NodeVolumeLimits plugin if you explicitly use those plugins in the scheduler config.

- Apimachinery/clock: This deletes the apimachinery/clock package. Please use k8s.io/utils/clock instead. ([#109752](https://github.com/kubernetes/kubernetes/pull/109752), [@MadhavJivrajani](https://github.com/MadhavJivrajani)) [SIG API Machinery]