Earning Points. Starwood's Preferred Guest program is fairly straightforward: the more nights you spend at participating hotels, the faster you'll earn a free night.
The mapper output (intermediate data) is stored on the Local file system (NOT HDFS) of each individual mapper nodes. This is typically a temporary directory location which can be setup in config by the hadoop administrator. The intermediate data is cleaned up after the Hadoop Job completes.
MapReduce is a programming model and an associated implementation for processing and generating large data sets with a parallel, distributed algorithm on a cluster.apReduce allows for distributed processing of the map and reduction operations. Provided that each mapping operation is independent of the others, all maps can be performed in parallel â though in practice this is limited by the number of independent data sources and/or the number of CPUs near each source.