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arXiv · 2111.09725

EDF-Like Scheduling for Self-Suspending Real-Time Tasks

Mario Günzel·Kuan-Hsun Chen·Jian-Jia Chen
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Abstract

In real-time systems, schedulability tests are utilized to provide timing guarantees. However, for self-suspending task sets, current suspension-aware schedulability tests are limited to Task-Level Fixed-Priority~(TFP) scheduling or Earliest-Deadline-First~(EDF) with constrained-deadline task systems. In this work we provide a unifying schedulability test for the uniprocessor version of Global EDF-Like (GEL) schedulers and arbitrary-deadline task sets. A large body of existing scheduling algorithms can be considered as EDF-Like, such as EDF, First-In-First-Out~(FIFO), Earliest-Quasi-Deadline-First~(EQDF) and Suspension-Aware EDF~(SAEDF). Therefore, the unifying schedulability test is applicable to those algorithms. Moreover, the schedulability test can be applied to TFP scheduling as well. Our analysis is the first suspension-aware schedulability test applicable to arbitrary-deadline sporadic real-time task systems under Job-Level Fixed-Priority (JFP) scheduling, such as EDF. Moreover, it is the first unifying suspension-aware schedulability test framework that covers a wide range of scheduling algorithms. Through numerical simulations, we show that the schedulability test outperforms the state of the art for EDF under constrained-deadline scenarios. Moreover, we demonstrate the performance of different configurations under EQDF and SAEDF.

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Mario Günzel, Kuan-Hsun Chen, Jian-Jia Chen. 2021-11-18. EDF-Like Scheduling for Self-Suspending Real-Time Tasks. https://arxiv.org/abs/2111.09725

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