Abstract: A method and apparatus for efficiently matching a large collection of user profiles against a large volume of data in a webcasting system. The invention generally includes in one embodiment four steps to parallelize the profiles. First, an initial profile set is partitioned into several subsets also referred to as sub-partitions using various heuristic methods. Second, each sub-partition is mapped onto one or more independent processing units. Each processing unit is not required to have equal processing performance. However, for best performance results, subset data should be mapped in one embodiment where the subset with a highest cost is mapped to a fastest processor, and the next highest cost subset mapped to the next fastest processor. Where appropriate, the invention evaluates the relative subset processing speed of each processor and adjusts future subset mapping based upon these evaluations.