Yes, you should look at JobInProgress class, and search for 'speculative'. JobTracker already has logic to launch speculative copies for tasks which are progressing at a degraded rate relative to other tasks.
+Vinod Kumar Vavilapalli
On Nov 25, 2012, at 2:18 PM, Samaneh Shokuhi wrote:
> Hi ,
> I need to detect the straggler map tasks specifically the last one to do
> some experiments .As i undestood job tracker is aware of all map tasks ,so
> is there any way to know the current running map task is the
> last(straggler) one ?