- kubelet
  - OS and Arch information is now recorded in `kubernetes.io/os` and `kubernetes.io/arch` labels on Node objects. The previous labels (`beta.kubernetes.io/os` and `beta.kubernetes.io/arch`) are still recorded, but are deprecated and targeted for removal in v1.18. ([#73333](https://github.com/kubernetes/kubernetes/pull/73333), [@yujuhong](https://github.com/yujuhong))

  // +optional
  optional EventSource source = 5;

  // The time at which the event was first recorded. (Time of server receipt is in TypeMeta.)
  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.Time firstTimestamp = 6;

  // The time at which the most recent occurrence of this event was recorded.
  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.Time lastTimestamp = 7;

  with `scheme: HTTPS` that encounter errors indicating the endpoint is actually
  using HTTP fall back to making the request over HTTP for compatibility with
  previous releases. When this happens, a `LifecycleHTTPFallback` event is recorded
  in the namespace of the pod and a `kubelet_lifecycle_handler_http_fallbacks_total`
  metric in the kubelet is incremented. Cluster administrators can opt out of the
  expanded lifecycle handler capabilities by setting

- Evictions due to pods breaching their ephemeral storage limits are now recorded by the `kubelet_evictions` metric and can be alerted on. ([#87906](https://github.com/kubernetes/kubernetes/pull/87906), [@smarterclayton](https://github.com/smarterclayton)) [SIG Node]

- Resolves non-deterministic behavior of the garbage collection controller when ownerReferences with incorrect data are encountered. Events with a reason of `OwnerRefInvalidNamespace` are recorded when namespace mismatches between child and owner objects are detected. The [kubectl-check-ownerreferences](https://github.com/kubernetes-sigs/kubectl-check-ownerreferences) tool can be run prior to upgrading to locate existing objects with invalid...

- Kube-apiserver: DELETECOLLECTION API requests are now recorded in metrics with the correct verb. ([#113133](https://github.com/kubernetes/kubernetes/pull/113133), [@sxllwx](https://github.com/sxllwx)) [SIG API Machinery]

- UpdateContainerResources is no longer recorded as a `container_status` operation. It now uses the label `update_container`. ([#75278](https://github.com/kubernetes/kubernetes/pull/75278), [@Nessex](https://github.com/Nessex))

- Kube-apiserver: errors decoding objects in etcd are now recorded in an `apiserver_storage_decode_errors_total` counter metric ([#114376](https://github.com/kubernetes/kubernetes/pull/114376), [@baomingwang](https://github.com/baomingwang)) [SIG API Machinery and Instrumentation]

        * At Request audit level or higher, an annotation with key "patch.webhook.admission.k8s.io/round_{round idx}_index_{order idx}" get logged with the JSON payload logging the patch sent by a webhook for given request.

- Fixed two scheduler metrics (pending_pods and schedule_attempts_total) not being recorded ([#87692](https://github.com/kubernetes/kubernetes/pull/87692), [@everpeace](https://github.com/everpeace)) [SIG Scheduling]
- Kubelet metrics have been changed to buckets.