HPA YAML

An autoscaling/v2 HPA defines the target object with scaleTargetRef, the bounds with minReplicas/maxReplicas, and the list of criteria with metrics:

apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
  name: api
spec:
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: api
  minReplicas: 2
  maxReplicas: 10
  metrics:
    - type: Resource
      resource:
        name: cpu
        target:
          type: Utilization
          averageUtilization: 70

An HPA can take several metrics; a separate replica count is calculated for each and the largest is chosen. Memory, custom application metrics (requests/second) and external metrics (queue length) can be used too:

  metrics:
    - type: Resource
      resource:
        name: cpu
        target: {type: Utilization, averageUtilization: 70}
    - type: Resource
      resource:
        name: memory
        target: {type: AverageValue, averageValue: 400Mi}