Real-Time Systems

, Volume 1, Issue 1, pp 27–60 | Cite as

Aperiodic task scheduling for Hard-Real-Time systems

  • Brinkley Sprunt
  • Lui Sha
  • John Lehoczky


A real-time system consists of both aperiodic and periodic tasks. Periodic tasks have regular arrival times and hard deadlines. Aperiodic tasks have irregular arrival times and either soft or hard deadlines. In this article, we present a new algorithm, the Sporadic Server algorithm, which greatly improves response times for soft deadline aperiodic tasks and can guarantee hard deadlines for both periodic and aperiodic tasks. The operation of the Sporadic Server algorithm, its performance, and schedulability analysis are discussed and compared with previously published aperiodic service algorithms.


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Copyright information

© Kluwer Academic Publishers 1989

Authors and Affiliations

  • Brinkley Sprunt
    • 1
  • Lui Sha
    • 2
    • 3
  • John Lehoczky
    • 4
  1. 1.Department of Electrical and Computer EngineeringCarnegie Mellon UniversityPittsburghUSA
  2. 2.Department of Computer ScienceCarnegie Mellon UniversityPittsburghUSA
  3. 3.Software Engineering InstituteCarnegie Mellon UniversityPittsburghUSA
  4. 4.Department of StatisticsCarnegie Mellon UniversityPittsburghUSA

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