Running multiple application from the same Application Master

[Krishna Kishore Bonagiri <wr...@gmail.com>]

Hi,

  I was reading on this link

http://hortonworks.com/blog/apache-hadoop-yarn-concepts-and-applications/

that we can implement an Application Master to manage multiple
applications. The text reads like this:

*It’s useful to remember that, in reality, every application has its own
instance of an ApplicationMaster. However, it’s completely feasible to
implement an ApplicationMaster to manage a set of applications (e.g.
ApplicationMaster for Pig or Hive to manage a set of MapReduce jobs). *

How is it possible? Do they have different application IDs and are they
treated as different applications on the cluster? What are the
positive/negative implications of it? Is it a recommended way?

Thanks,
Kishore