I was unable to find any information regarding relationship between mapred slots and number of cpus on the net. All I found was that it is advisable to schedule two processes for one cpu. If this is true, then for a slave node with dual core( two cpus) that runs datanode, tasktracker, hbase regionserver and zookeeper, theoretically there is no space to run an additional mapred task. Any comment on this is welcome.
In general what is the mapred slot and how is it related to number of cpu cores?
Thanks in advance.