Fwd: Problem in Understanding concept of Physical Cores

2015-07-19 Thread Aniruddh Sharma
and Regards Aniruddh -- Forwarded message -- From: Aniruddh Sharma asharma...@gmail.com Date: Fri, Jul 17, 2015 at 6:05 PM Subject: Re: Problem in Understanding concept of Physical Cores To: user user@spark.apache.org Dear Community Request to help on below queries

Re: Problem in Understanding concept of Physical Cores

2015-07-17 Thread Aniruddh Sharma
Dear Community Request to help on below queries they are unanswered. Thanks and Regards Aniruddh On Wed, Jul 15, 2015 at 12:37 PM, Aniruddh Sharma asharma...@gmail.com wrote: Hi TD, Request your guidance on below 5 queries. Following is the context of them that I would use to evaluate

Re: Problem in Understanding concept of Physical Cores

2015-07-15 Thread Aniruddh Sharma
Hi TD, Request your guidance on below 5 queries. Following is the context of them that I would use to evaluate based on your response. a) I need to decide whether to deploy Spark in Standalone mode or in Yarn. But it seems to me that Spark in Yarn is more parallel than Standalone mode (given

Re: Problem in Understanding concept of Physical Cores

2015-07-10 Thread Aniruddh Sharma
Hi TD, Thanks for elaboration. I have further doubts based on further test that I did after your guidance Case 1: Standalone Spark-- In standalone mode, as you explained,master in spark-submit local[*] implicitly, so it uses as creates threads as the number of cores that VM has, but User can

Re: Problem in Understanding concept of Physical Cores

2015-07-09 Thread Tathagata Das
Query 1) What spark runs is tasks in task slots, whatever is the mapping ot tasks to physical cores it does not matter. If there are two task slots (2 threads in local mode, or an executor with 2 task slots in distributed mode), it can only run two tasks concurrently. That is true even if the task

Problem in Understanding concept of Physical Cores

2015-07-08 Thread Aniruddh Sharma
Hi I am new to Spark. Following is the problem that I am facing Test 1) I ran a VM on CDH distribution with only 1 core allocated to it and I ran simple Streaming example in spark-shell with sending data on port and trying to read it. With 1 core allocated to this nothing happens in my

Re: Problem in Understanding concept of Physical Cores

2015-07-08 Thread Tathagata Das
There are several levels of indirection going on here, let me clarify. In the local mode, Spark runs tasks (which includes receivers) using the number of threads defined in the master (either local, or local[2], or local[*]). local or local[1] = single thread, so only one task at a time local[2]