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Oozie Coordinator Job Scheduling frequency

Sometimes you may see a situation where-in coordinator job says frequency in minutes for example say 60 but you can see the workflow jobs are running more frequently.

 On the OOZIE Web console you can see the ‘Created Time’ increments more frequently while ‘Nominal Time’ increments by an hour which is the interval you may want.

 The issue as here is that start date in coordinator xml is of past. So, in this scenario, Oozie will submit workflows for all the intervals that were missed starting from the start time till it gets in sync with current time. 

 **The nominal time is the actual time interval (hour) that the workflow is supposed to process.

So, In such a situation you might want to set Concurrency to decide how many actions to runs in parallel, or Execution strategy, that can be FIFO, LIFO, LAST Only, or Throttle to decide how many jobs can be in waiting status if one is already Running.

Example:

<controls>
<concurrency>1</concurrency>
<execution>LAST_ONLY</execution>
<throttle>1</throttle>
</controls> 

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