Cheng, Albert M. K.2019-09-182019-09-18August 2012017-08August 201Portions of this document appear in: Jiang, Yu, Albert MK Cheng, and Xingliang Zou. "Schedulability analysis for real-time P-FRP tasks under fixed priority scheduling." In 2015 IEEE 21st International Conference on Embedded and Real-Time Computing Systems and Applications, pp. 31-40. IEEE, 2015. And in: Zou, Xingliang, Albert MK Cheng, and Yu Jiang. "A non-work-conserving model for P-FRP fixed priority scheduling." In 2016 13th International Conference on Embedded Software and Systems (ICESS), pp. 12-17. IEEE, 2016. And in: Zou, Xingliang, Albert MK Cheng, Carlos Rincon, and Yu Jiang. "Multi-mode P-FRP Task Scheduling." In 2017 IEEE 20th International Symposium on Real-Time Distributed Computing (ISORC), pp. 150-157. IEEE, 2017.https://hdl.handle.net/10657/4791Functional Reactive Programming (FRP) is a declarative approach for modeling and building reactive systems. FRP has been shown to be an expressive formalism for building applications of computer graphics, computer vision, robotics, etc. Priority-based FRP (P-FRP) is a formalism that allows preemption of executing programs and guarantees real-time response. Since functional programs cannot maintain state and mutable data, changes made by programs that are preempted have to be rolled back. Hence in P-FRP, a higher priority task can preempt the execution of a lower priority task, but the preempted lower priority task will have to restart after the higher priority task has completed execution. This execution paradigm is called Abort-and-Restart (AR). Current real-time research is focused on preemptive of non-preemptive models of execution and several state-of-the-art methods have been developed to analyze the real-time guarantees of these models. Unfortunately, due to its transactional nature where preempted tasks are aborted and have to restart, the execution semantics of P-FRP does not fit into the standard definitions of preemptive or non-preemptive execution, and the research on the standard preemptive and non-preemptive may not applicable for the P-FRP AR model. Out of many research areas that P-FRP may demands, we focus on task scheduling which includes task and system modeling, priority assignment, schedulability analysis, response time analysis, improved P-FRP AR models, algorithms and corresponding software. In this work, we review existing results on P-FRP task scheduling and then present our research contributions: (1) a tighter feasibility test interval regarding the task release offsets as well as a linked list based algorithm and implementation for scheduling simulation; (2) P-FRP with software transactional memory-lazy conflict detection (STM-LCD); (3) a non-work-conserving scheduling model called Deferred Start; (4) a multi-mode P-FRP task model; (5) SimSo-PFRP, the P-FRP extension of SimSo - a SimPy-based, highly extensible and user friendly task generator and task scheduling simulator.application/pdfengThe author of this work is the copyright owner. UH Libraries and the Texas Digital Library have their permission to store and provide access to this work. UH Libraries has secured permission to reproduce any and all previously published materials contained in the work. Further transmission, reproduction, or presentation of this work is prohibited except with permission of the author(s).Real-time schedulingP-FRP2019-09-18Thesisborn digital