On Tue, Jul 14, 2015 at 10:40 AM, Shushant Arora <shushantarora09@gmail.com> wrote:
My understanding was --executor-cores(5 here) are maximum concurrent tasks possible in an executor and --num-executors (10 here)are no of executors or containers demanded by Application master/Spark driver program  to yarn RM.

--executor-cores requests cores from YARN. YARN is a resource manager, and you're requesting more resources than it has available, so it denies your request. If you want to make more than 4 cores available in your NMs, you need to change YARN's configuration.