Hi jkestelyn,   Thanks for the links,    But this has caused even more confusion! in Apache documentation for Capacity scheduling it is mentioned  When there is demand for these resources from queues running below capacity at a future point in time, as tasks scheduled on these resources complete, they will be assigned to applications on queues running below the capacity (pre-emption is not supported) Where as in Cloudera documentation : Job Scheduling in Apache Hadoop The Capacity Scheduler also supports configuring a wait time on each queue after which it is allowed to preempt other queues’ tasks if it is below its fair share Both are contradictory! So, once again, please clarify what is the actual behavior and the difference between these two scheduling methods. ... View more

I am not able to understand the difference between Fair and capacity scheduler. From what I have read I understood that they both are identical except for the fact that capacity scheduler has FIFO for the users within a queue. I am not sure what this means and if this is the complete truth. So it will be really helpful if someone can explain this is plain and simple words. ... View more