phases in tasks

[Pedro Costa]

Hi,

1 - A Task is composed by several phases:
STARTING, MAP/REDUCE, SHUFFLE, SORT, CLEANUP.

A JobTracker and a TaskTracker also has phases?

2 - It exists also the following phases
RUNNING,
                SUCCEEDED,
                FAILED,
                UNASSIGNED,
                KILLED,
                COMMIT_PENDING,
                FAILED_UNCLEAN,
                KILLED_UNCLEAN,

These phases also belong to the Map or Reduce tasks. So, it exists two
group of phases. Why is that?

Thanks,

-- 
Pedro