隨著多核心嵌入式裝置的普及, 能源消耗漸漸成為一項重要的議題。為了因應低耗能的
需求, 許多硬體平台支援動態電壓頻率調整來降低系統耗能, 調降處理器的頻率相對的
任務的反應時間(response time) 也會拉長, 在即時系統中, 任務必須在有限的時間內完
成, 導致處理器頻率調降受到限制。任務間共享資源在系統中是常見的, 共享資源的同
時也會帶來任務間不可預期的阻擋(blocking), 任務間的阻擋在多核心系統中會更加複
雜, 因為任務可以阻擋在其他核心執行的任務, 阻擋時間的拉長也會使頻率調降受到限
制。在本篇論文中提出了一個在多核心且允許資源共享的系統下, 彈性的低功率演算法,
可以在系統運行時新增任務、回收多餘執行時間的機制等。在最後會有實驗模擬以及平
台實做, 討論此篇論文在模擬上的成果以及實做上的可行性。

Energy-efficient multi-core system has become a very important issue, and the resource sharing between tasks is common. It is a challenge to reduce energy consumption by slowdown processor frequency because the unexpected blocking may leadmiss deadline. We propose a flexible Triple Speed algorithm to reduce the energy consumption. In this paper, we will introduce how Triple Speed to adapt to different synchronization protocol, add new tasks, and has reclaiming mechanism. Finally, a series of simulation experiment and real platform realized to verify the practicability of the Triple Speed algorithm.

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