Resolution: Won't Fix
Affects Version/s: 2.0.2-alpha
Fix Version/s: None
We have a M/R job that use Mapper + Combiner but have nothing to do in Reducer :
Bulk indexing of HBase data in ElasticSearch,
Map output is K / V : #bulk / json_data_to_be_indexed.
So job is launched maps work, combiners index and a reducer is created for nothing (sometimes waiting for other M/R job to free a tasktracker slot for reducer cf.
When we put ```job.setNumReduceTasks(0);``` in our job .run(), mapper are started but combiner are not used.