硬軟體特徵考量之省電即時程序排程

Energy-Efficient Real-Time Task Scheduling with the Considerations of Hardware and Software Characteristics

楊川岳(Chuan-Yue Yang)

指導教授 ： 郭大維

國立臺灣大學/電機資訊學院/資訊工程學研究所/博士(2010年)

https://doi.org/10.6342/NTU.2010.02913

摘要

在電子系統的軟硬體實做上，省電設計已成為一項重要的議題。動態電壓調節技術能夠有效地平衡系統的耗電與效能。可動態電壓調節的系統上的現存的研究大多針對最差工作執行時間來設計，而本論文則針對工作執行時間具有週期性規則的工作群組提出有效率的省電排程方法，該方法能以有限的記憶體空間逼近省電最佳化的排程結果。除了處理器之外，周邊設備也造成大量的耗電，因此省電排程也必須考慮周邊設備所造成的耗電。在我們的排程方法中，我們可以透過先佔的控制來減少周邊設備閒置的時間，進而降低周邊設備所造成的耗電。另外，因為漏電耗電的大小與系統的溫度息息相關，我們不同於以往的研究結果，探討漏電耗電量大小和溫度相關的系統上的省點排程方式，並提出一個系統化的方法來最佳化系統於平衡狀態下的耗電量。

關鍵字

功耗感知設計 ； 省電排程 ； 溫度感知排程 ； 即時系統 ； 工作排程

並列摘要

Energy-aware design for electronic systems has been an important issue in hardware and software implementations. Dynamic voltage scaling (DVS) techniques have been adopted to effectively trade the performance for the energy consumption. However, most existing research for energy-efficient design in DVS systems with real-time constraints focuses on tasks with worst-case execution times. In this dissertation, we propose two types of approaches to efficiently and effectively minimize the energy consumption to schedule a set of periodic real-time tasks with the multiframe property, in which the execution times of task instances are characterized by a vector of elements that are repeated. By assigning an execution speed to each task frame, the proposed frame-based approach can approximate the optimal solutions with limited memory space. As system devices often make a significant contribution to the power consumption of the entire system in reality, effective energy-efficient scheduling algorithms should consider not only the energy consumption of the processor but also the usages of devices. Thus, we propose scheduling algorithms in the management of task preemption to reduce the energy consumption of non-DVS devices. Moreover, leakage power consumption which depends on temperature contributes significantly to the overall power dissipation for systems that are manufactured in advanced deep sub-micron technology. Different from many previous results, we explore leakage-aware energy-efficient scheduling over processors with temperature-dependent leakage power consumption as the conclusion of this dissertation. Since the proposed pattern-based approach leads to a steady state with an equilibrium temperature, we develop a procedure to find the optimal pattern whose energy consumption in steady state is the minimum.

並列關鍵字

Power-Aware Design ； Energy-Efficient Scheduling ； Temperature-Aware Scheduling ； Real-Time System ； Task Scheduling

參考文獻

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