1. A computer-implemented method for processing a graph comprising graph data in a network comprising a plurality of individual processor-based machines, the method comprising: partitioning the graph into a plurality of partitions; assigning each partition to a respective machine of the plurality of machines; applying a density-based filter to each partition to produce a plurality of partitions of a filtered graph; applying a partial connectivity detector process to each of the partitions of the filtered graph to produce sub-clusters of nodes of the filtered graph; and merging the sub-clusters of nodes through a message based merge process.