On Energy-Optimal Voltage Scheduling for Fixed-Priority Hard Real-Time Systems

고정 우선순위 경성 실시간 시스템에 대한 최적의 전압 스케줄링

  • 윤한샘 (서울대학교 컴퓨터공학부) ;
  • 김지홍 (서울대학교 전기컴퓨터공학부)
  • Published : 2004.10.01

Abstract

We address the problem of energy-optimal voltage scheduling for fixed-priority hard real-time systems. First, we prove that the problem is NP-hard. Then, we present a fully polynomial time approximation scheme (FPTAS) for the problem. for any $\varepsilon$>0, the proposed approximation scheme computes a voltage schedule whose energy consumption is at most (1+$\varepsilon$) times that of the optimal voltage schedule. Furthermore, the running time of the proposed approximation scheme is bounded by a polynomial function of the number of input jobs and 1/$\varepsilon$. Experimental results show that the approximation scheme finds more efficient voltage schedules faster than the best existing heuristic.

본 논문에서는 고정 우선순위 경성 실시간 시스템에 대한 에너지 측면에서의 최적의 전압 스케줄링 문제를 고려한다. 먼저, 이 문제가 NP-hard임을 증명한다. 다음으로 이 문제에 대한 fully polynomial time approximation scheme(FPTAS)을 제시한다 제안한 FPTAS는 주어진 임의의 $\varepsilon$>0에 대해 에너지 소모량이 최적의 전압 스케줄에 비해 (1+$\varepsilon$)배 이내에 있는 전압 스케줄을 문제의 입력의 크기와 1/$\varepsilon$의 다항함수 이내의 시간에 계산해준다. 실험 결과, 제안된 FPTAS는 기존의 휴리스틱에 비해 더 효율적인 전압 스케줄을 더 빠른 시간에 찾아주었다.

Keywords

References

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