MapReduce v1 Job Resource Allocation

When a MapReduce v1 job is submitted to JobTracker, JobTracker determines which TaskTracker nodes can process the map and reduce tasks based on the available map and reduce slots. Map and reduce slots are allocated based on the memory available to process MapReduce V1 jobs, and the number of CPUs and Disks available to MapR-FS.

In general, you should not need to customize the number of map and reduce slots. However, you can configure the parameters that are used to calculate the values. For more information, see Customizing the MapReduce v1 Slot Calculation Parameters.

The following sections provide additional information about map and reduce slot calculation: