Best Practice: Identifying your Job from within the Container¶

Motivation¶

There may be use cases where your container may need to uniquely identify the Job it is currently running in. A typical use case is for saving Job artifacts under a unique name.

Run:AI provides environment variables you can use. These variables are guaranteed to be unique even if the Job is preempted or evicted and then runs again.

Identifying a Job¶

Run:AI provides the following environment variables:

• JOB_NAME - the name of the Job.
• JOB_UUID - a unique identifier for the Job.

Note that the Job can be deleted and then recreated with the same name. A Job UUID will be different even if the Job names are the same.

Identifying a Pod¶

With Hyperparameter Optimization, experiments are run as Pods within the Job. Run:AI provides the following environment variables to identify the Pod.

• POD_INDEX - An index number (0, 1, 2, 3....) for a specific Pod within the Job. This is useful for Hyperparameter Optimization to allow easy mapping to individual experiments. The Pod index will remain the same if restarted (due to a failure or preemption). Therefore, it can be used by the Researcher to identify experiments.
• POD_UUID - a unique identifier for the Pod. if the Pod is restarted, the Pod UUID will change.

Usage Example in Python¶

import os

jobName = os.environ['JOB_NAME']
jobUUID = os.environ['JOB_UUID']