Running batch jobs
Kubernetes has a support for running batch jobs. A Job is a daemon which watches your pod and makes sure it exited with exit status 0. If it did not for any reason, it will be restarted up to
backoffLimit number of times.
Since jobs in Nautilus are not limited in runtime, you can only run jobs with meaningful
command field. Running in manual mode (
command and manual start of computation) is prohibited.
Let’s run a simple job and get it’s result.
Create a job.yaml file and submit:
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: limits: memory: 200Mi cpu: 1 requests: memory: 50Mi cpu: 50m restartPolicy: Never backoffLimit: 4
Explore what’s running:
kubectl get jobs kubectl get pods
When job is finished, your pod will stay in Completed state, and Job will have COMPLETIONS field 1/1. For long jobs, the pods can have Error, Evicted, and other states until they finish properly or backoffLimit is exhausted.
Our job did not use any storage and outputed the result to STDOUT, which can be seen as our pod logs:
kubectl logs pi-<hash>
The pod and job will remain for you to come and look at for
ttlSecondsAfterFinished=604800 seconds (1 week) by default, and you can adjust this value in your job definition if desired.
You can use the more advanced example when ready.
Please make sure you did not leave any pods and jobs behind.