Submit work to a cluster - Amazon EMR

Submit work to a cluster

This section describes the methods that you can use to submit work to an Amazon EMR cluster. To submit work, you can add steps, or you can interactively submit Hadoop jobs to the primary node.

Consider the following rules of step behavior when you submit steps to a cluster:

  • A step ID can contain up to 256 characters.

  • You can have up to 256 PENDING and RUNNING steps in a cluster.

  • Even if you have 256 active steps running on a cluster, you can interactively submit jobs to the primary node. You can submit an unlimited number of steps over the lifetime of a long-running cluster, but only 256 steps can be RUNNING or PENDING at any given time.

  • With Amazon EMR versions 4.8.0 and later, except version 5.0.0, you can cancel pending steps. For more information, see Cancel steps.

  • With Amazon EMR versions 5.28.0 and later, you can cancel both pending and running steps. You can also choose to run multiple steps in parallel to improve cluster utilization and save cost. For more information, see Considerations for running multiple steps in parallel.

Note

For the best performance, we recommend that you store custom bootstrap actions, scripts, and other files that you want to use with Amazon EMR in an Amazon S3 bucket that is in the same AWS Region as your cluster.