- DynamicFakeClient now exposes its tracker via a `Tracker()` function ([#100085](https://github.com/kubernetes/kubernetes/pull/100085), [@markusthoemmes](https://github.com/markusthoemmes)) [SIG API Machinery]

 Extended resources cannot be overcommitted, so make sure that request and limit are equal
 if both are present in a container spec.

 - The default Bootstrap Token created with `kubeadm init` v1.8 expires
 and is deleted after 24 hours by default to limit the exposure of the
 valuable credential. You can create a new Bootstrap Token with
 `kubeadm token create` or make the default token permanently valid by specifying

- Exposes and sets a default timeout for the SubjectAccessReview client for DelegatingAuthorizationOptions ([#96152](https://github.com/kubernetes/kubernetes/pull/96152), [@p0lyn0mial](https://github.com/p0lyn0mial)) [SIG API Machinery and Cloud Provider]

- HPA controller exposes the following metrics from the kube-controller-manager. 
  - `metric_computation_duration_seconds`: The time(seconds) that the HPA controller takes to calculate one metric.

- `kubelet` now emits a metric for end-to-end pod startup latency, including image pull. ([#121041](https://github.com/kubernetes/kubernetes/pull/121041), [@ruiwen-zhao](https://github.com/ruiwen-zhao))
- `kubelet` now exposes latency metrics of different stages of the node startup. ([#118568](https://github.com/kubernetes/kubernetes/pull/118568), [@qiutongs](https://github.com/qiutongs))

### Documentation

!function(e,a){"object"==typeof exports&&"undefined"!=typeof module?module.exports=a():"function"==typeof define&&define.amd?define(a):e.moment=a()}(this,function(){"use strict";var e,n;function M(){return e.apply(null,arguments)}function i(e){return e instanceof Array||"[object Array]"===Object.prototype.toString.call(e)}function _(e){return null!=e&&"[object Object]"===Object.prototype.toString.call(e)}function h(e,a){return Object.prototype.hasOwnProperty.call(e,a)}function o(e){if(Object....

- Introduced the `scheduling.k8s.io/v1alpha1` Workload API to express workload-level scheduling requirements and allow the kube-scheduler to act on them. ([#134564](https://github.com/kubernetes/kubernetes/pull/134564), [@macsko](https://github.com/macsko)) [SIG API Machinery, Apps, CLI, Etcd, Scheduling and Testing]...

- Exposes and sets a default timeout for the SubjectAccessReview client for DelegatingAuthorizationOptions ([#96153](https://github.com/kubernetes/kubernetes/pull/96153), [@p0lyn0mial](https://github.com/p0lyn0mial)) [SIG API Machinery and Cloud Provider]

// https://www.iana.org/domains/root/db/expert.html
expert

// exposed : Binky Moon, LLC
// https://www.iana.org/domains/root/db/exposed.html
exposed

// express : Binky Moon, LLC
// https://www.iana.org/domains/root/db/express.html
express

// extraspace : Extra Space Storage LLC
// https://www.iana.org/domains/root/db/extraspace.html
extraspace

// fage : Fage International S.A.

### SIG Instrumentation

* Added prometheus cluster monitoring addon to kube-up. ([#62195](https://github.com/kubernetes/kubernetes/pull/62195), [@serathius](https://github.com/serathius))
* Kubelet now exposes a new endpoint, `/metrics/probes`, which exposes a Prometheus metric containing the liveness and/or readiness probe results for a container. ([#61369](https://github.com/kubernetes/kubernetes/pull/61369), [@rramkumar1](https://github.com/rramkumar1))