On Best-Effort Utility Accrual Real-Time Scheduling on Multiprocessors
نویسندگان
چکیده
We consider the problem of scheduling dependent real-time tasks for overloads on a multiprocessor system, yielding best-effort timing assurance. The application/scheduling model includes tasks with time/utility function time constraints, mutual exclusion constraints, and arbitrary arrival, execution-time and resource access behaviors, with the timeliness optimization objective of maximizing the total accrued utility while ensuring mutual exclusion constraints and deadlock-freedom. Since this problem is NP-hard, we develop a class of polynomial-time heuristic algorithms, called the Global Utility Accrual (GUA) class of algorithms, and present two algorithm instances, namely, Non-Greedy Global Utility Accrual (NG-GUA) and Greedy Global Utility Accrual (G-GUA). We establish several properties of the algorithms including conditions under which optimal total utility is accrued, mutual exclusion constraints are satisfied, and deadlock-freedom is achieved. We develop a Linux-based real-time kernel called ChronOS, extended from the CONFIG PREEMPT RT real-time Linux patch. ChronOS provides a framework for the implementation and plugging-in of a variety of multiprocessor schedulers. Our experimental study with ChronOS reveals the effectiveness of GUA algorithms under a broad range of workloads.
منابع مشابه
On Scheduling Exception Handlers in Dynamic Real-Time Systems
We consider the problem of scheduling exception handlers in real-time systems that operate under runtime uncertainties including those on execution times, activity arrivals, and failure occurrences. The application/scheduling model includes activities and their exception handlers that are subject to time/utility function (TUF) time constraints and an utility accrual (UA) optimality criterion. A...
متن کاملUtility Accrual Real-Time Scheduling and Synchronization on Single and Multiprocessors: Models, Algorithms, and Tradeoffs
متن کامل
On Multiprocessor Utility Accrual Real-Time Scheduling with Statistical Timing Assurances
We present the first Utility Accrual (or UA) real-time scheduling algorithm for multiprocessors, called gMUA. The algorithm considers an application model where real-time activities are subject to time/utility function time constraints, variable execution time demands, and resource overloads where the total activity utilization demand exceeds the total capacity of all processors. We establish s...
متن کاملUtility accrual real-time scheduling for multiprocessor embedded systems
We present the first Utility Accrual (or UA) real-time scheduling algorithm for multiprocessors, called global Multiprocessor Utility Accrual scheduling algorithm (or gMUA). The algorithm considers an application model where real-time activities are subject to time/utility function time constraints, variable execution time demands, and resource overloads where the total activity utilization dem...
متن کاملFault Recovery Mechanisms in Utility Accrual Real Time Scheduling Algorithm
In this paper, we proposed two recovery solutions over the existing error-free utility accrual scheduling algorithm known as General Utility Accrual Scheduling algorithm (or GUS) (Peng Li, 2004). A robust fault recovery algorithm called Backward Recovery GUS (or BRGUS) works by adapting the time redundancy model i.e., by re-executing the affected task after its transient error period is over. T...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2010