* The Kubelet's deprecated `--allow-privileged` flag now defaults to true. This enables users to stop setting `--allow-privileged` in order to transition to `PodSecurityPolicy`. Previously, users had to continue setting `--allow-privileged`, because the default was false. ([#63442](https://github.com/kubernetes/kubernetes/pull/63442), [@mtaufen](https://github.com/mtaufen))

        * `failure-domain.beta.kubernetes.io/region`
        * `[*.]kubelet.kubernetes.io/*`
        * `[*.]node.kubernetes.io/*`
    * Setting other `kubernetes.io/`- and `k8s.io/`-prefixed labels using the `--node-labels` flag will produce a warning in v1.13, and be disallowed in v1.15. Setting labels that are not prefixed with `kubernetes.io/` or `k8s.io/` is still permitted.

* Fix fetching pids running in a cgroup, which caused problems with OOM score adjustments & setting the /system cgroup ("misc" in the summary API). ([#36551](https://github.com/kubernetes/kubernetes/pull/36551), [@timstclair](https://github.com/timstclair))

### Non-recursive Volume Ownership (FSGroup) graduates to Beta

By default, the `fsgroup` setting, if specified, recursively updates permissions for every file in a volume on every mount. This can make mount, and pod startup, very slow if the volume has many files. 

- Kubernetes 1.23 is now built with go1.19.4. To match behavior of previous Kubernetes 1.23 patch releases:
  - `kube-apiserver` defaults the GOGC setting to 63, to approximate go1.17 garbage collection memory performance in heavily loaded API servers

  
  kubelet also ignores an error during opening `/dev/kmsg`.
  This feature gate also allows kube-proxy to ignore an error during setting `RLIMIT_NOFILE`.
  

  qualified domain name (FQDN) of a Pod is set as hostname of its containers. 
  In Linux containers, this means setting the FQDN in the hostname field of the 
  kernel (the nodename field of struct utsname).  In Windows containers, this
  means setting the this means setting the registry value of hostname for the registry key HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Services\\Tcpip\\Parameters to FQDN. 

  Setting feature gate MultiCIDRRangeAllocator=true, determines whether the MultiCIDRRangeAllocator controller can be used, while the kube-controller-manager flag below will pick the active controller.

  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
  
  Please use the following format for linking documentation:
  - [KEP]: <link>
  - [Usage]: <link>
  - [Other doc]: <link>

* kube-controller-manager: Fixes bug setting headless service labels on endpoints ([#85361](https://github.com/kubernetes/kubernetes/pull/85361), [@liggitt](https://github.com/liggitt))



# v1.16.3

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