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Energy-Efficient Scheduling of Periodic Real-Time Tasks on Lightly Loaded Multicore Processors
March 2012 (vol. 23 no. 3)
pp. 530-537
Wan Yeon Lee, Dongduk Women's University, Seoul
For lightly loaded multicore processors that contain more processing cores than running tasks and have dynamic voltage and frequency scaling capability, we address the energy-efficient scheduling of periodic real-time tasks. First, we introduce two energy-saving techniques for the lightly loaded multicore processors: exploiting overabundant cores for executing a task in parallel with a lower frequency and turning off power of rarely used cores. Next, we verify that if the two introduced techniques are supported, then the problem of minimizing energy consumption of real-time tasks while meeting their deadlines is NP-hard on a lightly loaded multicore processor. Finally, we propose a polynomial-time scheduling scheme that provides a near minimum-energy feasible schedule. The difference of energy consumption between the provided schedule and the minimum-energy schedule is limited. The scheme saves up to 64 percent of the processing core energy consumed by the previous scheme that executes each task on a separate core.

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Index Terms:
Energy minimization, multicore processor, periodic real-time task, scheduling, dynamic voltage and frequency scaling.
Wan Yeon Lee, "Energy-Efficient Scheduling of Periodic Real-Time Tasks on Lightly Loaded Multicore Processors," IEEE Transactions on Parallel and Distributed Systems, vol. 23, no. 3, pp. 530-537, March 2012, doi:10.1109/TPDS.2011.87
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