Brute-force determination of multiprocessor schedulability for sets of sporadic hard-deadline tasks

Abstract

This report describes a necessary and sufficient test for the schedulability of a set of sporadic hard-deadline tasks on a multiprocessor platform, using any of a variety of scheduling policies including global fixed task-priority and earliest-deadline-first (EDF). The contribution is to establish an upper bound on the computational complexity of this problem, for which no algorithm has yet been described. The compute time and storage complexity of the algorithm, which performs an exhaustive search of a very large state space, make it practical only for tasks sets with very small integer periods. However, as a research tool, it can provide a clearer picture than has been previously available of the real success rates of global preemptive priority scheduling policies and low-complexity sufficient tests of schedulability. © Springer-Verlag Berlin Heidelberg 2007.