Reduction to Uniprocessor (RUN) is a global optimal scheduling algorithm capable of efficiently generating schedules for independent periodic tasks. When tasks share resources other than processors, the only known solution designed for RUN is the Server Based Locking Protocol (SBLP). However, by restricting preemptive access to shared resources, SBLP potentially decreases schedulability. In this paper we rather employ a more flexible approach by using the Multiprocessor resource sharing Protocol (MrsP) as the underline mechanism. Making the rules of both RUN and MrsP compatible with each other is one of our contributions. We name our solution MrsP-RUN. Further, although MrsP is claimed to work with both partitioned and globally scheduled systems, to the best of our knowledge MrsP-RUN is the first solution employing MrsP in global scheduling. Another contribution in this paper comes from better exploring task packaging heuristics so as to improve schedulability. Under RUN, tasks are packed into servers and these need to be set up taking possible task blocking time into account. We show that our task packing improves system schedulability even when applied to SBLP. MrsP-RUN was implemented on Linux Textbed for Multiprocessor Scheduling in Real-Time systems (Litmus^RT). Experimental results show improvements in terms of schedulability, task preemptions and migrations while overall runtime overhead is comparable with those in SBLP.

单处理器缩减 (RUN) 是一种全局最优调度算法，能够有效地为独立的周期性任务生成调度。当任务共享处理器以外的资源时，专为 RUN 设计的唯一已知解决方案是基于服务器的锁定协议 (SBLP)。然而，通过限制对共享资源的抢先访问，SBLP 可能会降低可调度性。在本文中，我们宁愿采用更灵活的方法，使用多处理器资源共享协议（MrsP）作为底层机制。使 RUN 和 MrsP 的规则相互兼容是我们的贡献之一。我们将我们的解决方案命名为 MrsP-RUN。此外，尽管 MrsP 声称可以与分区系统和全局调度系统一起使用，但据我们所知，MrsP-RUN 是第一个在全局调度中使用 MrsP 的解决方案。本文的另一个贡献来自于更好地探索任务打包启发式，以提高可调度性。在 RUN 下，任务被打包到服务器中，并且在设置这些服务器时需要考虑可能的任务阻塞时间。我们表明，即使应用于 SBLP，我们的任务打包也可以提高系统的可调度性。 MrsP-RUN 在 Linux Textbed 上实现，用于实时系统中的多处理器调度 (Litmus ^RT )。实验结果表明，在可调度性、任务抢占和迁移方面有所改进，而总体运行时开销与 SBLP 相当。