本論文分析輸入輸出裝置消耗非必要能源的原因並且提出即時裝置排程系統(簡
稱JDS)幫助裝置將非必要性耗能降到最低。JDS 為在線的裝置排程演算法，其包
含Iterative slack allocator 與Dynamic handler 兩部分。Iterative slack
allocator 將slack 分配給每個工作以降低錯誤預期工作起始時間而造成的非必
要裝置耗能，Dynamic handler 在系統運行的時候動態調整每個工作的slack 以
消除unnecessary slack 所造成的非必要裝置耗能。JDS 的比較對象為目前最先
進的在線裝置排程演算法，簡稱EEDS。實驗結果顯示JDS 最多比EEDS 節省33%
的裝置總耗電量，其中使用JDS 的實驗裝置因閒置而造成的耗電量比EEDS 的耗
電量減少了72%。

In this paper, we analyze the issues that cause a device to consume more energy
than it really needs and propose Just-in-time Device Scheduler (JDS), an online
device scheduling algorithm, to address the issues. JDS consists of two major
components: Iterative slack allocator and Dynamic handler. Iterative slack
allocator statically assign slack to the tasks to reduce the energy consumed by
device due to misprediction of job execution. Dynamic handler fine-tunes slack for
the jobs in runqueue at run-time to reduce the energy waste incurred by unnecessary
slack. JDS is compared with EEDS, the state-of-the-art online device scheduling
algorithm, in evaluation. The experimental results show that JDS saves up to 33%
of device energy consumption and 72% of device idle energy compared to EEDS.

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