determining which region a mapper processed

When a MapReduce job is run against HBase, a mapper is created for each region (using TableInputFormat). Is there a way look at the history and determine which region a given mapper ran against? Or can I rely on the mapper number being the same as the region number? TIA Brian

Re: determining which region a mapper processed

You shouldn't rely on mapper number. Each mapper can log the first key it processes. Cheers On Jul 20, 2014, at 7:52 AM, Brian Jeltema brian.jelt...@digitalenvoy.net wrote: When a MapReduce job is run against HBase, a mapper is created for each region (using TableInputFormat). Is there