Conditions for On-line Scheduling of Hard Real-Time Tasks on Multiprocessors

In this paper we consider the problem ofon-linescheduling ofhard real-timetasks onmultipleprocessors. For a given set of ready tasks, one can propose many schedules. These schedules, however, may not necessarily be suitable for on-line scheduling. A suitable on-line schedule is one which can accommodate any future task set when it arrives. The traditional approach to solve the on-line scheduling problem is to propose a heuristic, and then to prove its effectiveness by comparing it with existing heuristics using simulation. No attempt has, however, been made to obtain a condition on the current schedule which when satisfied will permit one to schedule an arbitrary future task. In this paper, we aim at developing such a condition on the current schedule for the set of ready tasks which when satisfied can guarantee an on-line schedule for any futurefeasibletask set.