Cut Costs Running Batch Jobs on ACK Serverless with Preemptible Instances - Container Service for Kubernetes

ACK Serverless runs batch jobs on demand — billing stops when the pod lifecycle ends, so you don't need to reserve nodes or expand the cluster for burst workloads. For cost-sensitive batch tasks, you can further reduce costs by using preemptible instances.

Prerequisites

Before you begin, make sure you have:

Run a job

Step 1: Create the job manifest

Create a file named job.yaml with the following content:

apiVersion: batch/v1
kind: Job
metadata:
  name: pi
spec:
  template:
    spec:
      containers:
      - name: pi
        image: perl
        command: ["perl",  "-Mbignum=bpi", "-wle", "print bpi(2000)"]
        resources:
          requests:
            cpu: 16
            memory: 32Gi
      restartPolicy: Never
  backoffLimit: 4

This example computes pi to 2,000 decimal places using 16 CPUs and 32 GiB of memory.

Step 2: Deploy the job

kubectl apply -f job.yaml

Step 3: Check the job status

Run the following command to check the state of the pod:

kubectl get pod

Expected output:

NAME       READY   STATUS      RESTARTS   AGE
pi-4f7w5   0/1     Completed   0          80s

Run the following command to view detailed information about the state of the pod:

kubectl describe pod

Expected output:

Name:               pi-4f7w5
Namespace:          default
Priority:           0
PriorityClassName:  <none>
Node:               virtual-kubelet-cn-hongkong-b/10.10.66.169
...
Events:
  Type    Reason                 Age   From          Message
  ----    ------                 ----  ----          -------
  Normal  SuccessfulMountVolume  114s  kubelet, eci  MountVolume.SetUp succeeded for volume "default-token-8k4jz"
  Normal  Pulling                113s  kubelet, eci  pulling image "perl"
  Normal  Pulled                 64s   kubelet, eci  Successfully pulled image "perl"
  Normal  Created                64s   kubelet, eci  Created container
  Normal  Started                64s   kubelet, eci  Started container

Use preemptible instances

Preemptible instances can reduce computing costs. To use a preemptible instance, add the k8s.aliyun.com/eci-spot-strategy: SpotAsPriceGo annotation to the pod template:

apiVersion: batch/v1
kind: Job
metadata:
  name: pi
spec:
  template:
    metadata:
      annotations:
        k8s.aliyun.com/eci-spot-strategy: SpotAsPriceGo
    spec:
      containers:
      - name: pi
        image: perl
        command: ["perl",  "-Mbignum=bpi", "-wle", "print bpi(2000)"]
        resources:
          requests:
            cpu: 16
            memory: 32Gi
      restartPolicy: Never
  backoffLimit: 4

For more information, see Use preemptible instances.

What's next

Learn about Kubernetes Job concepts to configure parallelism, completion counts, and failure handling.