* Reduced the CPU and memory requests for the Metrics Server Nanny sidecar container to free up unused resources.  ([#57252](https://github.com/kubernetes/kubernetes/pull/57252), [@kawych](https://github.com/kawych))

- Kubelet: a "maxParallelImagePulls" field can now be specified in the kubelet configuration file to control how many image pulls the kubelet can perform in parallel. ([#115220](https://github.com/kubernetes/kubernetes/pull/115220), [@ruiwen-zhao](https://github.com/ruiwen-zhao)) [SIG API Machinery, Node and Scalability]

* Free up CPU and memory requested but unused by Metrics Server Pod Nanny. ([#57252](https://github.com/kubernetes/kubernetes/pull/57252), [@kawych](https://github.com/kawych))

- Using exec auth plugins with kubectl no longer results in warnings about constructing many client instances from the same exec auth config. ([#97857](https://github.com/kubernetes/kubernetes/pull/97857), [@liggitt](https://github.com/liggitt)) [SIG API Machinery and Auth]

- kubeadm: remove misleading error message regarding image pulling ([#66658](https://github.com/kubernetes/kubernetes/pull/66658), [@dixudx](https://github.com/dixudx))
- kubeadm: Pull sidecar and dnsmasq-nanny images when using kube-dns ([#66499](https://github.com/kubernetes/kubernetes/pull/66499), [@rosti](https://github.com/rosti))

- Authentication token cache size is increased (from 4k to 32k) to support clusters with many nodes or many namespaces with active service accounts. ([#83643](https://github.com/kubernetes/kubernetes/pull/83643), [@lavalamp](https://github.com/lavalamp))

- Fixed a bug where pv recycler failed to scrub volume with too many files in the directory due to hitting ARG_MAX limit with rm command (#117189). ([#117283](https://github.com/kubernetes/kubernetes/pull/117283), [@defo89](https://github.com/defo89)) [SIG Cloud Provider and Storage]

* Mark the LBaaS v1 of OpenStack cloud provider deprecated. ([#52821](https://github.com/kubernetes/kubernetes/pull/52821), [@FengyunPan](https://github.com/FengyunPan))
* Mark image as deliberately optional in v1 Container struct.  Many objects in the Kubernetes API inherit the container struct and only Pods require the field to be set. ([#48406](https://github.com/kubernetes/kubernetes/pull/48406), [@gyliu513](https://github.com/gyliu513))

- Recursive Volume Ownership OnRootMismatch Option: Add a new “OnRootMismatch” policy that can help shorten the mount time for volumes that require ownership change and have many directories and files.

### Other notable announcements

SIG Network is moving IPv6 to Beta in Kubernetes 1.18, after incrementing significantly the test coverage with new CI jobs.

* Improve efficiency of preemption logic in clusters with many pending pods. ([#72895](https://github.com/kubernetes/kubernetes/pull/72895), [@bsalamat](https://github.com/bsalamat))