<P> By default, jobs that are uncategorized go into a default pool . Pools have to specify the minimum number of map slots, reduce slots, as well as a limit on the number of running jobs . </P> <P> The capacity scheduler was developed by Yahoo . The capacity scheduler supports several features that are similar to those of the fair scheduler . </P> <Ol> <Li> Queues are allocated a fraction of the total resource capacity . </Li> <Li> Free resources are allocated to queues beyond their total capacity . </Li> <Li> Within a queue, a job with a high level of priority has access to the queue's resources . </Li> </Ol> <Li> Queues are allocated a fraction of the total resource capacity . </Li>

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