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Quasi-partitioned scheduling: optimality and adaptation in multiprocessor real-time systems


We describe a new algorithm, called quasi-partitioned scheduling (QPS), capable of scheduling any feasible system composed of independent implicit-deadline sporadic tasks on identical processors. QPS partitions the system tasks into subsets, each of which is either scheduled by EDF on a single processor or by a set of servers on two or more processors. More precisely, QPS uses an efficient scheme to switch between partitioned EDF and global-like scheduling rules in response to system load variation, providing dynamic adaptation in the system. Extensive simulation compares QPS favorably against related work, showing that it has very low preemption and migration overheads.

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This work has been funded by CNPq and CAPES. The authors would like to thank to Geoffrey Nelissen for his comments about U-EDF and his help in its simulations.

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Correspondence to Ernesto Massa.

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Massa, E., Lima, G., Regnier, P. et al. Quasi-partitioned scheduling: optimality and adaptation in multiprocessor real-time systems. Real-Time Syst 52, 566–597 (2016). https://doi.org/10.1007/s11241-016-9251-6

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  • Real time
  • Scheduling
  • Multiprocessor
  • Optmality