Multiprocessor Schedulability Analysis for Self - Suspending Task Systems ∗

In many real-time systems, tasks may experience suspension delays. The problem of analyzing task systems with such suspensions on multiprocessors has been relatively unexplored and is thought to be difficult (as it is on uniprocessors). In this paper, hard/soft multiprocessor schedulability tests for arbitrary-deadline sporadic self-suspending task systems are presented for both global EDF and global fixed-priority scheduling. The presented analysis shows that suspensions surprisingly have a rather limited impact on schedulability. In experiments presented herein, the proposed schedulability tests proved to be superior to prior tests. Moreover, for arbitrary-deadline ordinary sporadic task systems with no suspensions, the proposed analysis for fixed-priority scheduling improves upon prior analysis.