HorizontalPodAutoscaler
autoscaling/v2
Namespaced
HorizontalPodAutoscaler is the configuration for a horizontal pod autoscaler, which automatically manages the replica count of any resource implementing the scale subresource based on the metrics specified.
RBAC Verbs
create
delete
deletecollection
get
list
patch
update
watch
Properties
| Field | Type | Required? | Description |
|---|---|---|---|
| apiVersion | string | APIVersion defines the versioned schema of this representation of an object. Servers should convert recognized schemas to the latest internal value, and may reject unrecognized values. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#resources |
| Field | Type | Required? | Description |
|---|---|---|---|
| kind | string | Kind is a string value representing the REST resource this object represents. Servers may infer this from the endpoint the client submits requests to. Cannot be updated. In CamelCase. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds |
| Field | Type | Required? | Description |
|---|---|---|---|
| metadata | object | metadata is the standard object metadata. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata | |
| metadata.annotations | object | Annotations is an unstructured key value map stored with a resource that may be set by external tools to store and retrieve arbitrary metadata. They are not queryable and should be preserved when modifying objects. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/annotations | |
| metadata.creationTimestamp | string | CreationTimestamp is a timestamp representing the server time when this object was created. It is not guaranteed to be set in happens-before order across separate operations. Clients may not set this value. It is represented in RFC3339 form and is in UTC. Populated by the system. Read-only. Null for lists. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata | |
| metadata.deletionGracePeriodSeconds | integer | Number of seconds allowed for this object to gracefully terminate before it will be removed from the system. Only set when deletionTimestamp is also set. May only be shortened. Read-only. | |
| metadata.deletionTimestamp | string | DeletionTimestamp is RFC 3339 date and time at which this resource will be deleted. This field is set by the server when a graceful deletion is requested by the user, and is not directly settable by a client. The resource is expected to be deleted (no longer visible from resource lists, and not reachable by name) after the time in this field, once the finalizers list is empty. As long as the finalizers list contains items, deletion is blocked. Once the deletionTimestamp is set, this value may not be unset or be set further into the future, although it may be shortened or the resource may be deleted prior to this time. For example, a user may request that a pod is deleted in 30 seconds. The Kubelet will react by sending a graceful termination signal to the containers in the pod. After that 30 seconds, the Kubelet will send a hard termination signal (SIGKILL) to the container and after cleanup, remove the pod from the API. In the presence of network partitions, this object may still exist after this timestamp, until an administrator or automated process can determine the resource is fully terminated. If not set, graceful deletion of the object has not been requested. Populated by the system when a graceful deletion is requested. Read-only. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata | |
| metadata.finalizers | array | Must be empty before the object is deleted from the registry. Each entry is an identifier for the responsible component that will remove the entry from the list. If the deletionTimestamp of the object is non-nil, entries in this list can only be removed. Finalizers may be processed and removed in any order. Order is NOT enforced because it introduces significant risk of stuck finalizers. finalizers is a shared field, any actor with permission can reorder it. If the finalizer list is processed in order, then this can lead to a situation in which the component responsible for the first finalizer in the list is waiting for a signal (field value, external system, or other) produced by a component responsible for a finalizer later in the list, resulting in a deadlock. Without enforced ordering finalizers are free to order amongst themselves and are not vulnerable to ordering changes in the list. | |
| metadata.generateName | string | GenerateName is an optional prefix, used by the server, to generate a unique name ONLY IF the Name field has not been provided. If this field is used, the name returned to the client will be different than the name passed. This value will also be combined with a unique suffix. The provided value has the same validation rules as the Name field, and may be truncated by the length of the suffix required to make the value unique on the server. If this field is specified and the generated name exists, the server will return a 409. Applied only if Name is not specified. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#idempotency | |
| metadata.generation | integer | A sequence number representing a specific generation of the desired state. Populated by the system. Read-only. | |
| metadata.labels | object | Map of string keys and values that can be used to organize and categorize (scope and select) objects. May match selectors of replication controllers and services. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/labels | |
| metadata.managedFields | array | ManagedFields maps workflow-id and version to the set of fields that are managed by that workflow. This is mostly for internal housekeeping, and users typically shouldn't need to set or understand this field. A workflow can be the user's name, a controller's name, or the name of a specific apply path like "ci-cd". The set of fields is always in the version that the workflow used when modifying the object. | |
| metadata.name | string | Name must be unique within a namespace. Is required when creating resources, although some resources may allow a client to request the generation of an appropriate name automatically. Name is primarily intended for creation idempotence and configuration definition. Cannot be updated. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/names#names | |
| metadata.namespace | string | Namespace defines the space within which each name must be unique. An empty namespace is equivalent to the "default" namespace, but "default" is the canonical representation. Not all objects are required to be scoped to a namespace - the value of this field for those objects will be empty. Must be a DNS_LABEL. Cannot be updated. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/namespaces | |
| metadata.ownerReferences | array | List of objects depended by this object. If ALL objects in the list have been deleted, this object will be garbage collected. If this object is managed by a controller, then an entry in this list will point to this controller, with the controller field set to true. There cannot be more than one managing controller. | |
| metadata.resourceVersion | string | An opaque value that represents the internal version of this object that can be used by clients to determine when objects have changed. May be used for optimistic concurrency, change detection, and the watch operation on a resource or set of resources. Clients must treat these values as opaque and passed unmodified back to the server. They may only be valid for a particular resource or set of resources. Populated by the system. Read-only. Value must be treated as opaque by clients and . More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#concurrency-control-and-consistency | |
| metadata.selfLink | string | Deprecated: selfLink is a legacy read-only field that is no longer populated by the system. | |
| metadata.uid | string | UID is the unique in time and space value for this object. It is typically generated by the server on successful creation of a resource and is not allowed to change on PUT operations. Populated by the system. Read-only. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/names#uids |
| Field | Type | Required? | Description |
|---|---|---|---|
| spec | object | Required | spec is the specification for the behaviour of the autoscaler. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#spec-and-status. |
| spec.behavior | object | behavior configures the scaling behavior of the target in both Up and Down directions (scaleUp and scaleDown fields respectively). If not set, the default HPAScalingRules for scale up and scale down are used. | |
| spec.behavior.scaleDown | object | scaleDown is scaling policy for scaling Down. If not set, the default value is to allow to scale down to minReplicas pods, with a 300 second stabilization window (i.e., the highest recommendation for the last 300sec is used). | |
| spec.behavior.scaleDown.policies | array | policies is a list of potential scaling polices which can be used during scaling. If not set, use the default values: - For scale up: allow doubling the number of pods, or an absolute change of 4 pods in a 15s window. - For scale down: allow all pods to be removed in a 15s window. | |
| spec.behavior.scaleDown.selectPolicy | string | selectPolicy is used to specify which policy should be used. If not set, the default value Max is used. | |
| spec.behavior.scaleDown.stabilizationWindowSeconds | integer | stabilizationWindowSeconds is the number of seconds for which past recommendations should be considered while scaling up or scaling down. StabilizationWindowSeconds must be greater than or equal to zero and less than or equal to 3600 (one hour). If not set, use the default values: - For scale up: 0 (i.e. no stabilization is done). - For scale down: 300 (i.e. the stabilization window is 300 seconds long). | |
| spec.behavior.scaleDown.tolerance | Quantity | tolerance is the tolerance on the ratio between the current and desired metric value under which no updates are made to the desired number of replicas (e.g. 0.01 for 1%). Must be greater than or equal to zero. If not set, the default cluster-wide tolerance is applied (by default 10%). For example, if autoscaling is configured with a memory consumption target of 100Mi, and scale-down and scale-up tolerances of 5% and 1% respectively, scaling will be triggered when the actual consumption falls below 95Mi or exceeds 101Mi. | |
| spec.behavior.scaleUp | object | scaleUp is scaling policy for scaling Up. If not set, the default value is the higher of: * increase no more than 4 pods per 60 seconds * double the number of pods per 60 seconds No stabilization is used. | |
| spec.behavior.scaleUp.policies | array | policies is a list of potential scaling polices which can be used during scaling. If not set, use the default values: - For scale up: allow doubling the number of pods, or an absolute change of 4 pods in a 15s window. - For scale down: allow all pods to be removed in a 15s window. | |
| spec.behavior.scaleUp.selectPolicy | string | selectPolicy is used to specify which policy should be used. If not set, the default value Max is used. | |
| spec.behavior.scaleUp.stabilizationWindowSeconds | integer | stabilizationWindowSeconds is the number of seconds for which past recommendations should be considered while scaling up or scaling down. StabilizationWindowSeconds must be greater than or equal to zero and less than or equal to 3600 (one hour). If not set, use the default values: - For scale up: 0 (i.e. no stabilization is done). - For scale down: 300 (i.e. the stabilization window is 300 seconds long). | |
| spec.behavior.scaleUp.tolerance | Quantity | tolerance is the tolerance on the ratio between the current and desired metric value under which no updates are made to the desired number of replicas (e.g. 0.01 for 1%). Must be greater than or equal to zero. If not set, the default cluster-wide tolerance is applied (by default 10%). For example, if autoscaling is configured with a memory consumption target of 100Mi, and scale-down and scale-up tolerances of 5% and 1% respectively, scaling will be triggered when the actual consumption falls below 95Mi or exceeds 101Mi. | |
| spec.maxReplicas | integer | Required | maxReplicas is the upper limit for the number of replicas to which the autoscaler can scale up. It cannot be less that minReplicas. |
| spec.metrics | array | metrics contains the specifications for which to use to calculate the desired replica count (the maximum replica count across all metrics will be used). The desired replica count is calculated multiplying the ratio between the target value and the current value by the current number of pods. Ergo, metrics used must decrease as the pod count is increased, and vice-versa. See the individual metric source types for more information about how each type of metric must respond. If not set, the default metric will be set to 80% average CPU utilization. | |
| spec.minReplicas | integer | minReplicas is the lower limit for the number of replicas to which the autoscaler can scale down. It defaults to 1 pod. minReplicas is allowed to be 0 if the alpha feature gate HPAScaleToZero is enabled and at least one Object or External metric is configured. Scaling is active as long as at least one metric value is available. | |
| spec.scaleTargetRef | object | Required | scaleTargetRef points to the target resource to scale, and is used to the pods for which metrics should be collected, as well as to actually change the replica count. |
| spec.scaleTargetRef.apiVersion | string | apiVersion is the API version of the referent | |
| spec.scaleTargetRef.kind | string | Required | kind is the kind of the referent; More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds |
| spec.scaleTargetRef.name | string | Required | name is the name of the referent; More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/names/#names |
| Field | Type | Required? | Description |
|---|---|---|---|
| status | object | status is the current information about the autoscaler. | |
| status.conditions | array | conditions is the set of conditions required for this autoscaler to scale its target, and indicates whether or not those conditions are met. | |
| status.currentMetrics | array | currentMetrics is the last read state of the metrics used by this autoscaler. | |
| status.currentReplicas | integer | currentReplicas is current number of replicas of pods managed by this autoscaler, as last seen by the autoscaler. | |
| status.desiredReplicas | integer | Required | desiredReplicas is the desired number of replicas of pods managed by this autoscaler, as last calculated by the autoscaler. |
| status.lastScaleTime | string | lastScaleTime is the last time the HorizontalPodAutoscaler scaled the number of pods, used by the autoscaler to control how often the number of pods is changed. | |
| status.observedGeneration | integer | observedGeneration is the most recent generation observed by this autoscaler. |
Sample Manifest
apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
name: nginx
spec:
scaleTargetRef:
apiVersion: apps/v1
kind: Deployment
name: nginx
minReplicas: 2
maxReplicas: 10
metrics:
- type: Resource
resource:
name: cpu
target:
type: Utilization
averageUtilization: 70
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