I'm working on a workflow that has both Hive and Java actions. Very often we have been noticing that there is a few minutes delay between Java action start time and the job submission time. We don't see that with Hive jobs, meaning Hive jobs seem to be submitted almost immediately after they are started. The Java jobs do not do much and so they finish successfully in seconds after they are submitted but the time between start and submission seem to be very night ( 4 -5 minutes). We are using fair scheduler and the there are enough mapper/reducer slots available. But still even if it's a resource problem the Hive jobs should also show delay between start and submission but they don't ! Java jobs are very simple jobs and they don't process any files etc and basically used to call a web service and they spawn only single mapper and no reducers where are the Hive jobs creates hundreds of mapper/reducer tasks but still there is not delay between start and submission. We are not able to figure out why oozie is not submitting the Java job immediately. Any ideas?