EKS - Vertical Pod Autoscaling (VPA)¶

Step-01: Introduction¶

The Kubernetes Vertical Pod Autoscaler automatically adjusts the CPU and memory reservations for your pods to help "right size" your applications.
This adjustment can improve cluster resource utilization and free up CPU and memory for other pods.

Step-02: Pre-requisite - Metric server¶

Metric server should be installed & ready, we have done that as part of HPA

Step-03: Deploy the Vertical Pod Autoscaler (VPA)¶

# Clone Repo
git clone https://github.com/kubernetes/autoscaler.git

# Navigate to VPA
cd autoscaler/vertical-pod-autoscaler/

# Uninstall VPA (if we are using old one)
./hack/vpa-down.sh

# Install new version of VPA
./hack/vpa-up.sh

# Verify VPA Pods
kubectl get pods -n kube-system

Step-04: Review & Deploy our Application Manifests (Deployment & Service)¶

Make a note of resources we have defined spec.containers.resources.requests.

limits we define in VPA definition

        resources:
          requests:
            cpu: "5m"       
            memory: "5Mi"

Kubernetes-Manifests¶

01-VPA-DemoApplication.yml02-VPA-Manifest.yml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: vpa-demo-deployment
  labels:
    app: vpa-nginx
spec:
  replicas: 4
  selector:
    matchLabels:
      app: vpa-nginx
  template:
    metadata:
      labels:
        app: vpa-nginx
    spec:
      containers:
      - name: vpa-nginx
        image: stacksimplify/kubenginx:1.0.0
        ports:
        - containerPort: 80
        resources:
          requests:
            cpu: "5m"       
            memory: "5Mi"            
---
apiVersion: v1
kind: Service
metadata:
  name: vpa-demo-service-nginx
  labels:
    app: vpa-nginx
spec:
  type: NodePort
  selector:
    app: vpa-nginx
  ports:
  - port: 80
    targetPort: 80
    nodePort: 31232

apiVersion: "autoscaling.k8s.io/v1beta2"
kind: VerticalPodAutoscaler
metadata:
  name: kubengix-vpa
spec:
  targetRef:
    apiVersion: "apps/v1"
    kind: Deployment
    name: vpa-demo-deployment
  resourcePolicy:
    containerPolicies:
      - containerName: '*'
        minAllowed:
          cpu: 5m
          memory: 5Mi
        maxAllowed:
          cpu: 1
          memory: 500Mi
        controlledResources: ["cpu", "memory"]

Deploy¶

# Deploy Application
kubectl apply -f kube-manifests/01-VPA-DemoApplication.yml

# List Pods, Deploy & Service
kubectl get pod,svc,deploy

# Describe Pod
kubectl describe pod <pod-name>

# Access Application (If our NodeGroup is in Public Subnet, if not ignore)
kubectl get nodes -o wide
http://<Worker-Node-Public-IP>:31232

AWS EKS - Elastic Kubernetes Service - Masterclass¶

Step-05: Create & Deploy VPA manifest¶

Create VPA Manifest¶

Create a VPA manifest for our above Application which we deployed just now.

apiVersion: "autoscaling.k8s.io/v1beta2"
kind: VerticalPodAutoscaler
metadata:
  name: kubengix-vpa
spec:
  targetRef:
    apiVersion: "apps/v1"
    kind: Deployment
    name: vpa-demo-deployment
  resourcePolicy:
    containerPolicies:
      - containerName: '*'
        minAllowed:
          cpu: 5m
          memory: 5Mi
        maxAllowed:
          cpu: 1
          memory: 500Mi
        controlledResources: ["cpu", "memory"]

Deploy VPA Manifest¶

# Deploy
kubectl apply -f kube-manifests/02-VPA-Manifest.yml

# List VPA
kubectl get vpa

# Describe VPA
kubectl describe vpa kubengix-vpa

Step-06: Generate Load¶

Open 3 more new terminals and execute below 3 load generation commands

# Terminal 1 - List and watch pods
kubectl get pods -w

# Terminal 2 - Generate Load
kubectl run --generator=run-pod/v1 apache-bench -i --tty --rm --image=httpd -- ab -n 500000 -c 1000 http://vpa-demo-service-nginx.default.svc.cluster.local/

# Terminal 3 - Generate Load
kubectl run --generator=run-pod/v1 apache-bench2 -i --tty --rm --image=httpd -- ab -n 500000 -c 1000 http://vpa-demo-service-nginx.default.svc.cluster.local/

# Terminal 4 - Generate Load
kubectl run --generator=run-pod/v1 apache-bench3 -i --tty --rm --image=httpd -- ab -n 500000 -c 1000 http://vpa-demo-service-nginx.default.svc.cluster.local/

Step-07: Describe pods which were re-launched by VPA Updater¶

# List Pods
kubectl get pods

# Describe pods
kubectl describe pod <recently-relaunched-pod>

Step-08: Important Nodes about VPA:¶

VPA Updater can re-launch new pod with updated CPU and Memory when you atleast have 2 pods in a deployment.
If we have only one pod, unless we manually delete that pod, it will not launch new pod with VPA recommended CPU and memory considerign the application availability scenario.

Step-09: Clean-Up¶

kubectl delete -f kube-manifests/