Run A CronJob

This page shows you how to run a CronJob in a Kubernetes cluster with Kueue enabled.

The intended audience for this page are batch users.

Before you begin

Make sure the following conditions are met:

• A Kubernetes cluster is running.
• The kubectl command-line tool has communication with your cluster.
• Kueue is installed.
• The cluster has quotas configured.

0. Identify the queues available in your namespace

Run the following command to list the LocalQueues available in your namespace.

kubectl -n default get localqueues
# Or use the 'queues' alias.
kubectl -n default get queues

The output is similar to the following:

NAME         CLUSTERQUEUE    PENDING WORKLOADS
user-queue   cluster-queue   3

The ClusterQueue defines the quotas for the Queue.

1. Define the Job

Running a CronJob in Kueue is similar to running a CronJob in a Kubernetes cluster without Kueue. However, you must consider the following differences:

• You should set the JobTemplate in CronJob in a suspended state, as Kueue will decide when it’s the best time to start the Job.
• You have to set the Queue you want to submit the Job to. Use the kueue.x-k8s.io/queue-name label in jobTemplate.metadata
• You should include the resource requests for each Job Pod.
• You should set the spec.concurrencyPolicy to control the concurrency policy. The default is Allow. You can also set it to Forbid to prevent concurrent runs.
• You should set the spec.startingDeadlineSeconds to control the deadline for starting the Job. The default is no deadline.

Here is a sample CronJob with three Pods that just sleep for 10 seconds. The CronJob runs every minute.

apiVersion: batch/v1
kind: CronJob
metadata:
  name: sample-cronjob
  namespace: default
spec:
  schedule: "* * * * *"
  jobTemplate:
    metadata:
      labels:
        kueue.x-k8s.io/queue-name: user-queue
    spec:
      parallelism: 3
      completions: 3
      template:
        spec:
          containers:
          - name: dummy-job
            image: gcr.io/k8s-staging-perf-tests/sleep:v0.0.3
            args: ["10s"]
            resources:
              requests:
                cpu: 1
                memory: "200Mi"
          restartPolicy: Never

2. Run the CronJob

You can run the CronJob with the following command:

kubectl create -f sample-cronjob.yaml

Internally, Kueue will create a corresponding Workload for each run of the Job with a matching name.

kubectl -n default get workloads

The output will be similar to the following:

NAME                                QUEUE        ADMITTED BY     AGE
job-sample-cronjob-28373362-0133d   user-queue   cluster-queue   69m
job-sample-cronjob-28373363-e2aa0   user-queue   cluster-queue   68m
job-sample-cronjob-28373364-b42ac   user-queue   cluster-queue   67m

You can also Monitoring Status of the Workload.