Workload assignment for global real-time scheduling on unrelated multicore platforms

Abstract

Heterogeneous MPSoCs are being used more and more, from cellphones to critical embedded systems. Most of those systems offer heterogeneous sets of identical cores. In this paper, we propose new results on the global scheduling approach. We extend fundamental global scheduling results on unrelated processors to results on unrelated multicore platforms, a more realistic model. Every discussed result is optimal regarding schedulability, and all but one have a polynomial time complexity. We introduce several methods to construct the workload assignment taking advantage of this new model. Thanks to the model, their produced schedule has a limited degree of migrations. The benefits of those methods are demonstrated using simulation. We also discuss the practical limitations of the global scheduling approach on unrelated platforms and argue that it is still worth investigating considering modern MPSoCs.