Precise Scheduling Mixed-Criticality Gang Tasks with Reserved Processors
Precise Scheduling Mixed-Criticality Gang Tasks with Reserved Processors
复制标题
DOI：
--
复制
发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Tianning She;Zhishan Guo;Kecheng Yang
中科院分区：
文献类型：
--
作者：
Tianning She;Zhishan Guo;Kecheng Yang
为了减轻为实时系统提供最坏情况保证所必需的分析悲观主义，混合临界（MC）调度被提出，其中一个任务参数可能与对应于多个系统运行模式的多个估计相关联。虽然MC调度的大量工作是针对在模式切换时丢弃或降级低关键任务，但最近的一种称为精确MC调度的模型旨在保留所有任务的完整执行。在精确MC调度中，应该通过增加处理平台的能力来处理模式切换时由高关键任务引起的额外工作负载。本文研究了群任务的精确MC调度问题，这类任务可能需要同时占用多个处理器来开始执行。特别地，我们关注全局最早截止日期优先与虚拟截止日期（GEDF-VD）调度。给出了用GEDF-VD方法精确调度MC组任务的充分可调度性检验。通过可调度性测试，我们还分析了给定系统中可以安全地保留多少处理器。
—To mitigate the analytic pessimism that is often necessary to provide the worst-case guarantees for real-time systems, mixed-criticality (MC) scheduling has been proposed, where a task parameter may be associated with multiple estimates corresponding to multiple system runtime modes. While a large body of work on MC scheduling is directed at dropping or degrading low-critical tasks at the mode switch, a recent model, called precise MC scheduling, aims at preserving the full execution of all tasks instead. In precise MC scheduling, the additional workload due to high-critical tasks at the mode switch should be dealt with by increasing the capability of the processing platform. In this paper, we investigate the problem of precise MC scheduling of gang tasks, which may require simultaneously occupying multiple processors to commence any execution. In particular, we focus on the global earliest-deadline-first with virtual deadlines ( GEDF-VD ) scheduling. We derive a sufficient schedulability test for precise scheduling MC gang tasks by GEDF-VD . By the schedulability test, we also present an analysis of how many processors can be safely reserved in a given system.