MR1 has the concept of "map and reduce slots" (i.e. different types of slots) - but it does not run maps in reducer allocated slots - they are exclusive for reducers of any job to run.
YARN, on which MR2 runs, has no notion of dedicated slots (for M or R types). On Sat, Dec 29, 2012 at 6:51 PM, Pedro Sá da Costa <psdc1...@gmail.com> wrote: > MapReduce framework has map and reduce slots, that are used to track which > tasks are running. When map tasks are just running, the reduce slots that > the job have will be filled by map tasks? > > -- > Best regards, -- Harsh J
