- Added warnings about workload resources (Pods, ReplicaSets, Deployments, Jobs, CronJobs, or ReplicationControllers) whose names are not valid DNS labels. ([#114412](https://github.com/kubernetes/kubernetes/pull/114412), [@thockin](https://github.com/thockin))

    - [Scheduling](#scheduling)
  - [Notable Features](#notable-features)
    - [Workloads API (apps/v1beta2)](#workloads-api-appsv1beta2)
      - [API Object Additions and Migrations](#api-object-additions-and-migrations)
      - [Behavioral Changes](#behavioral-changes)
      - [Defaults](#defaults)
    - [Workloads API (batch)](#workloads-api-batch)
      - [CLI Changes](#cli-changes)
      - [Scheduling](#scheduling-1)

alpha feature enables a node to surface multiple runtime options to support a variety of workload types.  Examples include native linux containers, and “sandboxed” containers that isolate the container from the host kernel.

The CustomCFSQuotaPeriod alpha feature enables node administrators to change the default period used to enforce CFS quota on a node.  This can improve performance for some workloads that experience latency while using CFS quota with the default measurement period.  Finally,...

    - [**Network**](#network-2)
    - [**Storage**](#storage-2)
    - [**Scheduling**](#scheduling-1)
    - [**Node**](#node-2)
  - [Notable Changes](#notable-changes)
    - [**Workloads API (apps/v1)**](#workloads-api-appsv1)
    - [**API Machinery**](#api-machinery-3)
      - [**Admission Control**](#admission-control)
      - [**API & API server**](#api-&-api-server)
      - [**Audit**](#audit)

extended lifetime so they remain valid even after a new refreshed token is provided. The metric `serviceaccount_stale_tokens_total` can be used to monitor for workloads that are depending on the extended lifetime and are continuing to use tokens even after a refreshed token is provided to the container. If that metric indicates no existing workloads are depending on extended lifetimes, injected token lifetime can be shortened to 1 hour by starting `kube-apiserver` with `--service-account-extend-token-expiration=false`....

- Pods which set `hostNetwork: true` and declare ports, get the `hostPort` field set automatically. Previously this would happen in the PodTemplate of a Deployment, DaemonSet or other workload API.  Now `hostPort` will only be set when an actual Pod is being created.  If this presents a problem, setting the feature gate "DefaultHostNetworkHostPortsInPodTemplates" to true will revert this behavior.  Please file a kubernetes bug if you need...

[Topology Manager feature](https://github.com/nolancon/website/blob/f4200307260ea3234540ef13ed80de325e1a7267/content/en/docs/tasks/administer-cluster/topology-manager.md) enables NUMA alignment of CPU and devices (such as SR-IOV VFs) that will allow your workload to run in an environment optimized for low-latency. Prior to the introduction of the Topology Manager, the CPU and Device Manager would make resource allocation decisions independent of each other. This could result in undesirable allocations on...

* Resolves spurious rollouts of workload controllers when upgrading the API server due to incorrect defaulting of an alpha procMount field in pods ([#78882](https://github.com/kubernetes/kubernetes/pull/78882), [@liggitt](https://github.com/liggitt))

## Changelog since v1.17.15

## Changes by Kind

### Feature

- Add a new flag to set priority for the kubelet on Windows nodes so that workloads cannot overwhelm the node there by disrupting kubelet process. ([#96159](https://github.com/kubernetes/kubernetes/pull/96159), [@ravisantoshgudimetla](https://github.com/ravisantoshgudimetla)) [SIG Node]

### Bug or Regression

    * Default value for expendable pod priority cutoff in GCP deployment of Cluster Autoscaler changed from 0 to -10.
    * action required: users deploying workloads with priority lower than 0 may want to use priority lower than -10 to avoid triggering scale-up.

### Other notable changes