is executed by subsequently breaking it down into pieces called
tasks. When a node in Hadoopcluster receives a job, it is able
to divide it, and run it in parallel over other nodes [12].
Here the data location problem is solved by the JobTracker
which communicates with the NameNode to help datanodes
to send tasks to near-data datanodes.
Let us note that this
processing in form of pairs is not a limitation to
processing which does not seem, at first glance, feasible in
map-reduce manner.
Indeed, MapReduce has been successfully
used in RDF/RDFS and OWL reasoning [21,22] and in structured
data querying [23].