Lab 07 - Verticle Pod Autoscaler

Before you begin, ensure OpenSSL is installed and is up to date on your system.

Clone the kubernetes/autoscaler GitHub repository and switch to path where VPA manifests are,

git clone https://github.com/kubernetes/autoscaler.git
cd autoscaler/vertical-pod-autoscaler/ 

deploy VPA as

./hack/vpa-up.sh

Create a VPA Policy

File: vote-vpa.yaml

---
apiVersion: "autoscaling.k8s.io/v1"
kind: VerticalPodAutoscaler
metadata:
  name: vote
  labels:
    role: vote
spec:
  # recommenders field can be unset when using the default recommender.
  # When using an alternative recommender, the alternative recommender's name
  # can be specified as the following in a list.
  # recommenders:
  #   - name: 'alternative'
  targetRef:
    apiVersion: "apps/v1"
    kind: Deployment
    name: vote
  updatePolicy:
    updateMode: "Auto"
  resourcePolicy:
    containerPolicies:
      - containerName: '*'
        minAllowed:
          cpu: 50m
          memory: 64Mi
        maxAllowed:
          cpu: 500
          memory: 512Mi
        controlledResources: ["cpu", "memory"]

apply

kubectl apply -f vote-vpa.yaml

watch

kubectl get vpa vote --watch

[sample output]

NAME   MODE   CPU   MEM   PROVIDED   AGE
vote   Auto                          5s
vote   Auto   50m   262144k   True       30s

Create a Load Test Job if not already present as,

file: loadtest-job.yaml

apiVersion: batch/v1
kind: Job
metadata:
  generateName: loadtest
spec:
  template:
    spec:
      containers:
      - name: siege
        image: schoolofdevops/loadtest:v1
        command: ["siege",  "--concurrent=1", "--benchmark", "--time=4m", "http://vote"]
      restartPolicy: Never
  backoffLimit: 4

and launch it as

kubectl create -f loadtest-job.yaml

This will launch a one off Job which would run for 4 minutes.

keep watching the following in differnt windows

terminal 1

kubectl get vpa vote --watch

terminal 2

kubectl get hpa vote --watch

you should see, both hpa and vpa doing complimentary jobs where, * HPA is launching new pods to ensure more requests are being served * VPA is updating the requests spec based on actual metrics

You could check the modified request spec by VPA by describing the one of the pods runnnig vote app

kubectl describe pod vote-xxxx-yyyy

   Restart Count:  0
    Limits:
      cpu:     1235m
      memory:  500Mi
    Requests:
      cpu:        247m
      memory:     262144k
    Environment:  <none>
    Mounts: