// as last seen by the autoscaler.
  optional int32 currentReplicas = 3;

  // desiredReplicas is the desired number of replicas of pods managed by this autoscaler,
  // as last calculated by the autoscaler.
  optional int32 desiredReplicas = 4;

  // currentMetrics is the last read state of the metrics used by this autoscaler.
  // +optional

  // as last seen by the autoscaler.
  optional int32 currentReplicas = 3;

  // desiredReplicas is the desired number of replicas of pods managed by this autoscaler,
  // as last calculated by the autoscaler.
  optional int32 desiredReplicas = 4;

  // currentMetrics is the last read state of the metrics used by this autoscaler.
  // +optional

  // currentReplicas is current number of replicas of pods managed by this autoscaler,
  // as last seen by the autoscaler.
  // +optional
  optional int32 currentReplicas = 3;

  // desiredReplicas is the desired number of replicas of pods managed by this autoscaler,
  // as last calculated by the autoscaler.
  optional int32 desiredReplicas = 4;

}

// list of horizontal pod autoscaler objects.
message HorizontalPodAutoscalerList {
  // Standard list metadata.
  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.ListMeta metadata = 1;

  // items is the list of horizontal pod autoscaler objects.
  repeated HorizontalPodAutoscaler items = 2;
}

// specification of a horizontal pod autoscaler.
message HorizontalPodAutoscalerSpec {

[SIG Autoscaling][] is responsible for autoscaling-related components,
such as the Horizontal Pod Autoscaler and Cluster Autoscaler.

For the 1.8 release, SIG Autoscaling continued to focus on stabilizing
features introduced in previous releases: the new version of the
Horizontal Pod Autoscaler API, which supports custom metrics, and
the Cluster Autoscaler, which provides improved performance and error reporting.

- [KCCM - service controller]: enabled connection draining for terminating pods upon node downscale by the cluster autoscaler. This is done by not reacting to the taint used by the cluster autoscaler to indicate that the node is going away soon, thus keeping the node referenced by the load balancer until the VM has been completely deleted. ([#115204](https://github.com/kubernetes/kubernetes/pull/115204),...

- Kube-controller-manager: the `horizontal-pod-autoscaler-upscale-delay` and `horizontal-pod-autoscaler-downscale-delay` flags have been removed (deprecated and non-functional since v1.12). ([#124948](https://github.com/kubernetes/kubernetes/pull/124948), [@SataQiu](https://github.com/SataQiu)) [SIG API Machinery, Apps and Autoscaling]...

- Restartable init containers resource in pod autoscaler are now calculated. ([#120001](https://github.com/kubernetes/kubernetes/pull/120001), [@qingwave](https://github.com/qingwave))

- Enabled `kube-controller-manager` to support '--concurrent-horizontal-pod-autoscaler-syncs' flag to set the number of horizontal pod autoscaler controller workers. ([#108501](https://github.com/kubernetes/kubernetes/pull/108501), [@zroubalik](https://github.com/zroubalik))

replicaCount | [replica count](https://kubernetes.io/docs/concepts/workloads/controllers/deployment/)
hpaSpec | [HorizontalPodAutoscaler](https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale/)
podDisruptionBudget | [PodDisruptionBudget](https://kubernetes.io/docs/concepts/workloads/pods/disruptions/#how-disruption-budgets-work)