Preemptive Uniprocessor Scheduling of Mixed-Criticality Sporadic Task Systems
Abstract
Systems in many safety-critical application domains are subject to certification requirements. For any given system, however, it may be the case that only a subset of its functionality is safety-critical and hence subject to certification; the rest of the functionality is non-safety-critical and does not need to be certified, or is certified to lower levels of assurance. The certification-cognizant runtime scheduling of such mixed-criticality systems is considered. An algorithm called EDF-VD (for Earliest Deadline First with Virtual Deadlines) is presented: this algorithm can schedule systems for which any number of criticality levels are defined. Efficient implementations of EDF-VD, as well as associated schedulability tests for determining whether a task system can be correctly scheduled using EDF-VD, are presented. For up to 13 criticality levels, analyses of EDF-VD, based on metrics such as processor speedup factor and utilization bounds, are derived, and conditions under which EDF-VD is optimal with respect to these metrics are identified. Finally, two extensions of EDF-VD are discussed that enhance its applicability. The extensions are aimed at scheduling a wider range of task sets, while preserving the favorable worst-case resource usage guarantees of the basic algorithm.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 06, 2015
- Source ID
- 10.1145/2699435
Entities
People
- Alberto Marchetti-spaccamela
- Gianlorenzo D'angelo
- Haohan Li
- Leen Stougie
- Sanjoy Baruah
- Suzanne Van Der Ster
- Vincenzo Bonifaci
Organizations
- Army Research Office
- Gran Sasso Science Institute
- National Science Foundation
- Sapienza University of Rome
- University of North Carolina
- Vrije Universiteit Amsterdam