We have demonstrated simple schedulability tests for EDF and DM scheduling on a homogeneous multiprocessor system with preperiod deadlines. These can be applied statically, or applied dynamically as an admission test. Besides extending and generalizing previously known utilization-based tests for EDF and RM multiprocessor schedulability by supporting pre-period deadlines, we also provide a distinct and independent proof technique.
In future work, we plan to look at how the utilization bounds presented here for dynamic processor assignment bear on the question of whether to use static or dynamic processor assignment[1,15,12]. We have some experience dating back to 1991[17]) with an implementation of a fixed-priority multiprocessor kernel with dynamic migration of tasks. However, that experience is now out of date, due to advances in processor architectures that have increased the penalty for moving a task between processors. That penalty has not been taken into account in the present. A more complete analysis will require consideration of the task migration penalty.