K8S FIO

Prepare fio image

• Use an official or community-provided fio image (e.g., ubuntu:fio, ensuring fio is pre-installed in the image)
• Build a custom image containing fio

  # Use Alpine Linux as the base image
  FROM alpine:latest
  
  # Install dependencies and FIO
  RUN apk add --no-cache fio
  
  # Set FIO working directory
  WORKDIR /data
  
  # Expose FIO server port (default 8765)
  EXPOSE 8765
  
  # Define the default command to run fio
  CMD ["fio"]
  

docker build -t alpine-fio -f fio_dockerfile .

docker run -it --rm --network=host alpine-fio fio --version

• Ensure k8s nodes can access local image

  # Run a Docker registry container in detached mode
  # -d: Runs the container in the background (detached mode)
  # -p 5000:5000: Maps port 5000 on the host to port 5000 in the container, allowing access to the registry
  # --restart=always: Automatically restarts the container if it stops or the host reboots
  # --name registry: Names the container "registry" for easy reference
  # registry:2: Uses the official Docker registry image (version 2)
  docker run -d -p 5000:5000 --restart=always --name registry registry:2
  
  # Tag the local alpine-fio image for pushing to the local registry
  # alpine-fio - The source image name (built locally on your machine)
  # localhost:5000/alpine-fio - The new tag, indicating the image will be pushed to the local registry at localhost:5000
  docker tag alpine-fio localhost:5000/alpine-fio
  
  # Push the tagged image to the local registry
  # localhost:5000/alpine-fio: The target registry and image name
  # This uploads the image to the registry running at localhost:5000, making it accessible to Kubernetes nodes
  docker push localhost:5000/alpine-fio
  

Deploy FIO Server

• Create fio-server.yaml

  apiVersion: apps/v1
  kind: Deployment
  metadata:
    name: fio-server
    namespace: default
  spec:
    replicas: 1
    selector:
      matchLabels:
        app: fio-server
    template:
      metadata:
        labels:
          app: fio-server
      spec:
        containers:
        - name: fio-server
          image: localhost:5000/alpine-fio
          imagePullPolicy: Always
          command: ["fio"]
          args: ["--server", "--port=8765"]
          ports:
          - containerPort: 8765
            name: fio-port
          volumeMounts:
          - name: fio-volume
            mountPath: /test
          securityContext:
            capabilities:
              add: ["SYS_ADMIN"]
        volumes:
        - name: fio-volume
          hostPath:
            path: /mnt/fio-test
            type: DirectoryOrCreate
  ---
  apiVersion: v1
  kind: Service
  metadata:
    name: fio-server-service
    namespace: default
  spec:
    selector:
      app: fio-server
    ports:
    - protocol: TCP
      port: 8765
      targetPort: 8765
    type: ClusterIP
  

• Deploy FIO Server

  kubectl apply -f fio-server.yaml
  

Wait for FIO Server Ready

kubectl wait --for=condition=available deployment/fio-server --timeout=300s

Create fio-client.yaml

• Create fio-client.yaml

  apiVersion: batch/v1
  kind: Job
  metadata:
    name: fio-client
    namespace: default
  spec:
    template:
      spec:
        containers:
        - name: fio-client
          image: localhost:5000/alpine-fio
          imagePullPolicy: Always
          command: ["fio", "--server=fio-server:8765"]
          args:
            - "--client=fio-server-service.default.svc.cluster.local"
            - "--name=test"        # Specifies the name of the test
            - "--ioengine=libaio"  # Sets the I/O engine to libaio (Linux native asynchronous I/O)
            - "--rw=read"          # I/O mode: sequential read (other options: write, randread, randwrite, etc.)
            - "--bs=8k"            # Block size for I/O operations (4 KiB in this case)
            - "--size=1M"          # Total size of the test file (1 GiB in this case)
            - "--numjobs=3"        # Number of parallel jobs/processes (1 job in this case)
            - "--runtime=150"      # Test runtime in seconds (60 seconds in this case)
            - "--direct=1"         # Enables direct I/O, bypassing the cache (1 = enabled)
          volumeMounts:
          - name: fio-volume
            mountPath: /test
          securityContext:
            capabilities:
              add: ["SYS_ADMIN"]
        volumes:
        - name: fio-volume
          hostPath:
            path: /mnt/fio-test
            type: DirectoryOrCreate
        restartPolicy: Never
    backoffLimit: 3
  

• Deploy FIO Client

  kubectl apply -f fio-client.yaml
  

Monitor FIO Progress

kubectl get pods -w

View FIO Log

• View FIO Server Log

  kubectl logs -f deployment/fio-server
  
  kubectl describe pod -l app=fio-server
  

• View FIO Client Log

  kubectl logs -f job/fio-client
  

Retrieve Results

# Get detailed JSON output
kubectl logs job/fio-client > fio-results.json

# Parse results
kubectl logs job/fio-client | jq '.jobs[] | {jobname: .jobname, read: .read, write: .write}'

Clean Up

• Delete Client

  kubectl delete job fio-client -n default
  

• Delete Server

  kubectl delete deployment fio-server -n default