Figure 5.

Schema of the Job-tree job system. In Job-tree, job a creates a set of jobs that perform a task in parallel. These jobs are collectively called the children of job a. The job also creates a follow-on job to be performed after all children have successfully completed. The follow-on job is responsible for cleaning up the input files created for the children and for any further processing. After job a ends successfully, the batch system runs the children. These jobs may, in turn, have children and follow-on jobs. Upon completion of all descendants, the follow-on job is run. The follow-on job may create more children.