COMP5426_Parallel Program_2013 Semester 1_lecture06-13

Workers are assigned work by the master

The master is started by the MapReduce Framework

Workers assigned map tasks read the input, parse it and invoke the user’s Map() method.

Intermediate key/value pairs are buffered in memory Periodically, buffered data is written to local disk (R files) Pseudo random partitioning function (e.g., (hash(k) mod R)