Program Speedup in a Heterogeneous Computing Network

Program speedup is an important measure of the performance of an algorithm on a parallel machine. Of particular importance is the near linear or superlinear speedup exhibited by the most performance-eecient algorithms for a given system. We describe network and program models for heterogeneous networks, deene notions of speedup and superlinear speedup, and observe that speedup consists of both heterogeneous and parallel components. We also consider the case of linear tasks, give a lower bound for the speedup, and show that there is no theoretical upper limit on heterogeneous speedup.