I think that he was trying to explain that in HDFS, you have a name node and then your data nodes. So you have the name node service on the name node and each data node has a data node service. When you run a map reduce job, you have a Job tracker that resides on the name node and controls the overall job. On each data node, where the jobs run in parallel, there exists a task tracker.
> Date: Tue, 29 Jun 2010 23:24:58 +0430 > Subject: Re: What are uses of taskTracker and JobTracker services? > From: [email protected] > To: [email protected] > > Thanks for reply. > > But we have different services for each of them, for example a service for > NameNode and a Service for JobTracker, are they doing separate things each > one? > > > > On Tue, Jun 29, 2010 at 10:20 PM, Allen Wittenauer <[email protected] > > wrote: > > > > > On Jun 29, 2010, at 8:07 AM, Sarah kho wrote: > > > > > Hi, > > > > > > Can you please let me know what are tasks that the taskTracker and > > > JobTracker performs? > > > > Pretty much the entirety of the MapReduce framework. You can think of it > > this way: > > > > > > HDFS <--> MR > > NameNode <--> JobTracker > > DataNode <--> TaskTracker _________________________________________________________________ The New Busy is not the old busy. Search, chat and e-mail from your inbox. http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_3
