Cold-start testing with KinD and OpenFaaS

COLD_START_TESTING_OPENFAAS.md

Download KinD binary for your platform and move it to /usr/local/bin:

https://github.com/kubernetes-sigs/kind/releases/tag/v0.6.1

Get k3sup

curl -sSLf https://get.k3sup.dev | sudo sh

Install OpenFaaS with aggressively-tuned probes / check-intervals

k3sup app install openfaas \
    --set basic_auth=true \
    --set generateBasicAuth=false \
    --set functionNamespace=openfaas-fn \
    --set openFaasImagePullPolicy=IfNotPresent \
    --set faasnetes.imagePullPolicy=IfNotPresent \
    --set gateway.scaleFromZero=true \
    --set faasIdler.dryRun=false \
    --set faasIdler.inactivityDuration=2m \
    --set faasnetes.readinessProbe.initialDelaySeconds=1 \
    --set faasnetes.readinessProbe.timeoutSeconds=1 \
    --set faasnetes.readinessProbe.periodSeconds=1 \
    --set faasnetes.livenessProbe.initialDelaySeconds=1 \
    --set faasnetes.livenessProbe.timeoutSeconds=1 \
    --set faasnetes.livenessProbe.periodSeconds=1
    
kubectl rollout status -n openfaas deploy/gateway

kubectl -n openfaas port-forward deploy/gateway 8080:8080 &

# Login and port-forward
PASSWORD=$(kubectl get secret -n openfaas basic-auth -o jsonpath="{.data.basic-auth-password}" | base64 --decode; echo)
echo -n $PASSWORD | faas-cli login --username admin --password-stdin

Deploy a function, invoke it and then scale it to zero:

faas-cli deploy --name pycho --image theaxer/pycho:latest --fprocess='python index.py'

kubectl rollout status -n openfaas-fn deploy/pycho

faas-cli invoke pycho <<< "hi there"

kubectl scale -n openfaas-fn deploy/pycho --replicas=0

sleep 10

Now invoke from cold:

time faas-cli invoke pycho <<< "hi there"

kubectl logs  -n openfaas deploy/gateway --tail 500 gateway|grep Scale

Thanks to Lucas Roesler / Alex Ellis for the instructions