Issue No. 10 - October (2007 vol. 56)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TC.2007.1072
In this paper, we consider timeliness and energy optimization in battery-powered dynamic embedded real-time systems, which must remain functional during an operation/mission with a bounded energy budget. We consider application activities that are subject to time/utility function time constraints, statistical assurance requirements on timeliness behavior, and an energy budget which cannot be exceeded at runtime. To account for the inevitable variability in activity arrivals in dynamic systems, we describe arrival behaviors using the unimodal arbitrary arrival model (UAM) . For such a model, we present a dynamic voltage scaling (DVS)-based CPU scheduling algorithm called the energy-bounded utility accrual algorithm (EBUA). Since the scheduling problem is intractable, EBUA allocates CPU cycles, scales clock frequency, and heuristically computes schedules using statistical estimates of cycle demands in polynomial time. We analytically establish EBUA's properties, including satisfaction of energy bounds, statistical assurances on individual activity timeliness behavior, optimal timeliness during underloads, and bounded time for mutually exclusively accessing shared non-CPU resources. Our simulation experiments validate our analytical results and illustrate the algorithm's effectiveness and superiority over past algorithms.
embedded systems, power aware computing, real-time systems, scheduling, utility programs,utility accrual real-time scheduling, unimodal arbitrary arrival model, energy bounds, energy optimization, battery-powered dynamic embedded real-time systems, utility function time constraints, statistical assurance requirements, timeliness behavior, dynamic voltage scaling, CPU scheduling algorithm, energy-bounded utility accrual algorithm, polynomial time,Time factors, Real time systems, Job listing service, Energy efficiency, Batteries, Voltage control, Dynamic scheduling,Real-time systems, energy-efficient scheduling, time/utility functions, utility accrual scheduling
"Utility Accrual Real-Time Scheduling Under the Unimodal Arbitrary Arrival Model with Energy Bounds", IEEE Transactions on Computers, vol. 56, no. , pp. 1358-1371, October 2007, doi:10.1109/TC.2007.1072