autoscaling

autoscaling value in Kubedeploy allows controlling the parameters for Horizontal Pod Autoscaler object.

Autoscaling can aid in maintaining low resource and platform cost utilization while retaining the capability to automatically enhance application throughput based on various scaling triggers.

Warning

For HPA to function correctly, pods must define at least resource requests, as they are used in calculating utilization based on the CPU and memory utilization of the pods. While HPA can be deployed for deployments without defined resource requests, scaling will remain disabled until resource requests are defined.

Available values for autoscaling in Kubedeploy:

autoscaling:
  enabled: false # (1)
  minReplicas: 1 # (2)
  maxReplicas: 10 # (3)
  targetCPUUtilizationPercentage: 80 # (4)
  targetMemoryUtilizationPercentage: # (5)
  behavior: {} # (6)

1. Enable autoscaling. Works only with Deployment and Statefulset deploymentMode
2. Minimum number of Pod replicas
3. Maximum number of Pod replicas
4. (int) Scaling target CPU utilization as percentage of resources.requests.cpu
5. (int) Scaling target memory utilization as percentage of resources.requests.mem
6. (Feature state: 1.2.0) (map) Define custom scaling behavior

Define simple autoscaling policy

nameOverride: my-app
image:
  repository: nginx
  tag: latest

resources:
  requests:
    cpu: 0.5
    memory: 128Mi

autoscaling:
  enabled: true
  minReplicas: 2
  maxReplicas: 10
  targetCPUUtilizationPercentage: 80

Deploy command

helm install webapp sysbee/kubedeploy -f values.yaml

In the above example we are defining deployment with resource requirements of 1/2 of CPU core.

HPA is then configured to watch the CPU utilization of this workload. If it hits 80% of requested CPU resources it will increase the number of replicas by one until average deployment CPU utilization either drops below 80% or maxReplicas is reached.

HPA will attempt to downscale underutilized deployments every 5 minutes if the average CPU utilization is below 80%.

Imporant

It's important to note that the utilization percentage is always calculated from resource requests, not limits. If you have higher limits, you can, for example, define a percentage of 200%, which would allow pods to burst beyond their resource requests before triggering scaling.

See also:

• resources