Support for limited-preemptive fixed-priority scheduling: – an evolutionary step still facing research challenges –

Fixed-priority preemptive scheduling (FPPS) has been the defacto
standard used in industry for real-time systems for the past decades.
Unfortunately, arbitrary preemptions during execution may lead
to inefficient memory use and high run-time overheads. Fixed-priority
scheduling (FPS) with limited preemptions (LP-FPS) has
therefore been proposed in the literature as a viable alternative
to FPPS, that reduces memory requirements, reduces the cost of
arbitrary preemptions, and may improve the schedulability of a task
set. In this paper, we propose to incorporate support for LP-FPS
in next generation operating systems for cyber-physical systems,
facilitating an evolution of systems. Even for the single processor
case, there are still analytical research challenges, however.