Simultaneous Multithreading Applied to Real Time

Authors Sims Hill Osborne, Joshua J. Bakita, James H. Anderson

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Author Details

Sims Hill Osborne
  • University of North Carolina, Chapel Hill, North Carolina, USA
Joshua J. Bakita
  • University of North Carolina, Chapel Hill, North Carolina, USA
James H. Anderson
  • University of North Carolina, Chapel Hill, North Carolina, USA

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Sims Hill Osborne, Joshua J. Bakita, and James H. Anderson. Simultaneous Multithreading Applied to Real Time. In 31st Euromicro Conference on Real-Time Systems (ECRTS 2019). Leibniz International Proceedings in Informatics (LIPIcs), Volume 133, pp. 3:1-3:22, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2019)


Existing models used in real-time scheduling are inadequate to take advantage of simultaneous multithreading (SMT), which has been shown to improve performance in many areas of computing, but has seen little application to real-time systems. The SMART task model, which allows for combining SMT and real time by accounting for the variable task execution costs caused by SMT, is introduced, along with methods and conditions for scheduling SMT tasks under global earliest-deadline-first scheduling. The benefits of using SMT are demonstrated through a large-scale schedulability study in which we show that task systems with utilizations 30% larger than what would be schedulable without SMT can be correctly scheduled.

Subject Classification

ACM Subject Classification
  • Computer systems organization → Real-time systems
  • Computer systems organization → Real-time system specification
  • Software and its engineering → Scheduling
  • Software and its engineering → Multithreading
  • real-time systems
  • simultaneous multithreading
  • soft real-time
  • scheduling algorithms


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