Abstract
Discrete scheduling is preferred over continuous scheduling for preemptive scheduling problems, however, classical continuous schedulability tests can not work effectively with discrete scheduling. This area of integrating discrete scheduling with continuous schedulability tests remains unexplored. Two contributions are made in this paper, firstly, an empty-slot method is introduced and extended to discrete schedulability analysis and secondly, an efficient exact feasibility test is proposed that has lower complexity in contrast to current feasibility tests in terms of reducing the number of scheduling points, where task feasibility is analyzed.