Resource sharing in edf-scheduled systems: A closer look

Resource sharing in priority-based systems can give rise to priority-inversion and blocking, wherein a job’s execu-tion is delayed because a lower-priority job holds some re-source that is needed for execution. The Stack Resource Policy (SRP) can be used to reduce such blocking in EDF-scheduled systems. An efficient implementation of an algo-rithm is presented for determining whether systems sched-uled in this manner are feasible. Some interesting proper-ties of such systems are derived. The technique of reduc-ing the duration of blocking by the replication of selected resources is explored: an algorithm is presented which de-termines the minimum amount of resource replication nec-essary to achieve specified blocking times