Scheduling Divisible Loads on Star and Tree Networks: Results and Open Problems

• Authors: Olivier Beaumont;Henri Casanova;Arnaud Legrand;Yves Robert;Yang Yang
• Venue: IEEE Transactions on Parallel and Distributed Systems
• Year: 2005

Many applications in scientific and engineering domains are structured as large numbers of independent tasks with low granularity. These applications are thus amenable to straightforward parallelization, typically in master-worker fashion, provided that efficient scheduling strategies are available. Such applications have been called divisible loads because a scheduler may divide the computation among worker processes arbitrarily, both in terms of number of tasks and of task sizes. Divisible load scheduling has been an active area of research for the last 15 years. A vast literature offers results and scheduling algorithms for various models of the underlying distributed computing platform. Broad surveys are available that report on accomplishments in the field. By contrast, in this paper, we propose a unified theoretical perspective that synthesizes previously published results, several novel results, and open questions, in a view to foster novel divisible load scheduling research. Specifically, we discuss both one-round and multiround algorithms, and we restrict our scope to the popular star and tree network topologies, which we study with both linear and affine cost models for communication and computation.