### Instrumentation

- Kube-proxy iptables probabilities are now more granular and will result in better distribution beyond 319 endpoints. ([#83599](https://github.com/kubernetes/kubernetes/pull/83599), [@robscott](https://github.com/robscott))

* kubelet `--cert-dir` now defaults to `/var/lib/kubelet/pki`, in order to ensure bootstrapped and rotated certificates persist beyond a reboot. resolves an issue in kubeadm with false-positive `/var/lib/kubelet is not empty` message during pre-flight checks ([#53317](https://github.com/kubernetes/kubernetes/pull/53317), [@liggitt](https://github.com/liggitt))

    * The specific behavior of the podGC controller to clean up terminated pods is still governed by the flag, but the podGC's responsibilities have evolved beyond just cleaning up terminated pods.
* Update grafana version used by default in kubernetes to 3.1.1 ([#35435](https://github.com/kubernetes/kubernetes/pull/35435), [@Crassirostris](https://github.com/Crassirostris))

- Troubleshooting: informers log handlers that take more than 100 milliseconds to process an object if the `DeltaFIFO` queue starts to grow beyond 10 elements. ([#103917](https://github.com/kubernetes/kubernetes/pull/103917), [@aojea](https://github.com/aojea))