Optimal rate-based scheduling on multiprocessors
STOC '02 Proceedings of the thiry-fourth annual ACM symposium on Theory of computing
Pfair scheduling: beyond periodic task systems
RTCSA '00 Proceedings of the Seventh International Conference on Real-Time Systems and Applications
A Theory of Rate-Based Execution
RTSS '99 Proceedings of the 20th IEEE Real-Time Systems Symposium
Mixed Pfair/ERfair scheduling of asynchronous periodic tasks
Journal of Computer and System Sciences
Efficient and flexible fair scheduling of real-time tasks on multiprocessors
Efficient and flexible fair scheduling of real-time tasks on multiprocessors
Real Time Scheduling Theory: A Historical Perspective
Real-Time Systems
Fair scheduling of dynamic task systems on multiprocessors
Journal of Systems and Software - Special issue: Parallel and distributed real-time systems
Euromicro-RTS'00 Proceedings of the 12th Euromicro conference on Real-time systems
An experimental comparison of different real-time schedulers on multicore systems
Journal of Systems and Software
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The earliest-pseudo-deadline-first (EPDF) Pfair algorithm is more efficient than other known Pfair scheduling algorithms, but is not optimal for scheduling recurrent real-time task systems on more than two identical processors. Although not optimal, EPDF may be preferable for real-time systems instantiated on less-powerful platforms, those with soft timing constraints, or those whose task composition can change at run-time. In prior work, Srinivasan and Anderson established a sufficient per-task utilization restriction for ensuring a tardiness of at most q quanta, where q=1, under EPDF. They also conjectured that under this algorithm, a tardiness bound of one quantum applies to task systems that are not subject to any restriction other than the obvious restrictions, namely, that the total system utilization not exceed the available processing capacity and per-task utilizations not exceed 1.0. In this paper, we present counterexamples that show that their conjecture is false and present sufficient per-task utilization restrictions that are more liberal than theirs. For ensuring a tardiness bound of one quantum, our restriction presents an improvement of 50% over the previous one.