configure and close are run for each task, mapper and reducer. The configure and close are NOT run on the combiner class.
On Mon, Jun 22, 2009 at 9:23 AM, Saptarshi Guha <saptarshi.g...@gmail.com>wrote: > Hello, > In a mapreduce job, a given map JVM will run N map tasks. Are the > configure and close methods executed for every one of these N tasks? > Or is configure executed once when the JVM starts and the close method > executed once when all N have been completed? > > I have the same question for the reduce task. Will it be run before > for every reduce task? And close is run when all the values for a > given key have been processed? > > We can assume there isn't a combiner. > > Regards > Saptarshi > -- Pro Hadoop, a book to guide you from beginner to hadoop mastery, http://www.amazon.com/dp/1430219424?tag=jewlerymall www.prohadoopbook.com a community for Hadoop Professionals
