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Title: Tardiness Bounds for Fixed-Priority Global Scheduling without Intra-Task Precedence Constraints
Fixed-priority multicore schedulers are often preferable to dynamic-priority ones because they entail less overhead, are easier to im-plement, and enable certain tasks to be favored over others. Underglobal fixed-priority (G-FP) scheduling, as applied to the standardsporadic task model, response times for low-priority tasks may beunbounded, even if total task-system utilization is low. In this paper,it is shown that this negative result can be circumvented if differentjobs of the same task are allowed to execute in parallel. In particu-lar, a response-time bound is presented for task systems that allowintra-task parallelism. This bound merely requires that total utiliza-tion does not exceed the overall processing capacity—individualtask utilizations need not be further restricted. This result impliesthat G-FP is optimal for scheduling soft real-time tasks that requirebounded tardiness, if intra-task parallelism is allowed  more » « less
Award ID(s):
1717589
PAR ID:
10108197
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Proceedings of the 26th International Conference on Real-Time Networks and Systems
Page Range / eLocation ID:
8-18
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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