CronHPA

CronHPA is an operator to update HPA resources based on schedules. For example, you can decrease min replicas in the night-time and increase it in the day-time.

Here's a CronHPA example.

apiVersion: cron-hpa.dtaniwaki.github.com/v1alpha1
kind: CronHorizontalPodAutoscaler
metadata:
  name: cron-hpa-example
spec:
  template:
    spec:
      scaleTargetRef:
        apiVersion: apps/v1
        kind: Deployment
        name: cron-hpa-nginx
      minReplicas: 3
      maxReplicas: 10
      metrics:
      - type: Resource
        resource:
          name: cpu
          target:
            type: Utilization
            averageUtilization: 50
  scheduledPatches:
  - name: daytime
    schedule: "0 8 * * *"
    timezone: "Asia/Tokyo"
  - name: nighttime
    schedule: "0 22 * * *"
    timezone: "Asia/Tokyo"
    patch:
      minReplicas: 1 # Less minimum replicas.
      - type: Resource
        resource:
          name: cpu
          target:
            type: Utilization
            averageUtilization: 70 # More conservative scaling.

How to use CronHPA

Disable CronHPA temporarily

Mark the target HPA resource as below to temporarily skip getting CronHPA's update.

apiVersion: autoscaling/v2beta2
kind: HorizontalPodAutoscaler
metadata:
  annotations:
    cron-hpa.dtaniwaki.github.com/skip: "true"
...

Prerequisites

• golangci-lint v1.42.1

Build

Build and load the Docker image to your cluster.

$ make docker-build

# run a command to load the image to your cluster.

If you use a kind cluster, there's a useful shortcut.

$ make kind-load

Deployment

Install the CRD to the cluster.

$ make install

Deploy a controller to the cluster.

$ make deploy

Usage

Now, deploy the samples.

$ make deploy-samples

You will see sample HPA and deployment in the current context, maybe default depending on your env. The HPA resource gets updated periodically by the CronHPA.

Contributing

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request

Copyright

Copyright (c) 2021 Daisuke Taniwaki. See LICENSE for details.