Could someone please clarify on the below queries? Regards, Praveen
On Thu, Jan 5, 2012 at 9:59 PM, Praveen Sripati <praveensrip...@gmail.com>wrote: > Hi, > > I had been going through the MRv2 documentation and have the following > queries > > 1) Let's say that an InputSplit is on Node1 and Node2. > > Can the ApplicationMaster ask the ResourceManager for a container either > on Node1 or Node2 with an OR condition? > > 2) > The Scheduler receives periodic information about the resource usages > on allocated resources from the NodeManagers. The Scheduler also makes > available status of completed Containers to the appropriate > ApplicationMaster. > > What's the use of NM sending the resource usages to the scheduler? > > Why can't the NM directly talk to the AM about the completed containers? > Does any information pass from NM to AM? > > 3) >The Map-Reduce ApplicationMaster has the following components: > > TaskUmbilical – The component responsible for receiving heartbeats and > status updates form the map and reduce tasks. > > Does the communication happen directly between the container and the AM?If > yes, the task completion status could also be sent from the container to > the AM. > > 4) > The Hadoop Map-Reduce JobClient polls the ASM to obtain information > about the MR AM and then directly talks to the AM for status, counters etc. > > Once the Job is completed the AM goes down, what happens to the Counters? > What is the flow of the Counter (Container -> NM -> AM)? > > 5) If a new YARN application is created. How can the NM trust the request > from AM? > > 6) > MapReduce NextGen uses wire-compatible protocols to allow different > versions of servers and clients to communicate with each other. > > What is meant by the `wire-compatible protocols` and how is it > implemented? > > 7) > The computation framework (ResourceManager and NodeManager) is > completely generic and is free of MapReduce specificities. > > Is this the reason for adding auxiliary services for shuffling to the NM? > > Regards, > Praveen >
