CSDL Home R RTAS 2013 2013 IEEE 19th Real-Time and Embedded Technology and Applications Symposium (RTAS)
April 9, 2013 to April 11, 2013
Insup Lee , Department of Computer and Information Sciences, University of Pennsylvania
In this paper, we introduce a technique for improving the schedulability of real-time embedded systems with fixed-priority scheduling. Our technique uses shapers to reduce the resource interference between higher-priority and lower-priority tasks, and thus enables more lower-priority tasks to be scheduled. We present a closed-form solution for the optimal greedy shaper for periodic tasks with jitter, as well as a schedulability condition for tasks in the presence of shapers. We also discuss two applications of greedy shapers: In compositional scheduling frameworks, shapers can help optimize the resource interfaces of real-time components, and in mixed-criticality systems, they can reduce deadline misses of low-criticality tasks while preserving schedulability of high-criticality tasks, even with lower priorities. We demonstrate the utility of our technique through an evaluation based on randomly generated workloads.
Insup Lee, "Improving schedulability of fixed-priority real-time systems using shapers", RTAS, 2013, 2013 IEEE 19th Real-Time and Embedded Technology and Applications Symposium (RTAS), 2013 IEEE 19th Real-Time and Embedded Technology and Applications Symposium (RTAS) 2013, pp. 217-226, doi:10.1109/RTAS.2013.6531094