臺灣博碩士論文加值系統

可變速率裝置之省電考量是一個針對目前電腦所使用的網路卡裝置(LAN Device) 所設計的新的省電構思考量。它不只遵循目前工業界所使用的PCI-Express規格，而且更提供了一個省電設計與想法。在此研究中我們不僅設計新的硬體達到省電的目的，而其驅動軟體的時間區間(Time-Slice)設計，則提供了一個最短優先權的服務方式，此舉使得裝置不但具備省電能力而且又不致切換過度而造成浪費，並兼顧基本服務效能。在未來延伸性的應用上，其他的裝置(如VGA、USB、SATAT)仍可套用此方法在設計考量上。實驗結果證實我們的設計與方法，在模擬裝置的實驗上具有良好的省電效果。

Dynamic power management has been adopted in many systems to reduce the power consumption by changing the system state dynamically. This thesis explores energy efficiency for systems equipped with PCI Express devices, which are designed for low power consumption and high performance, compared to corresponding PCI devices. We propose a dynamic power management mechanism and a management policy for energy-efficiency considerations. A case study is exploited for a variable-bit-rate (VBD) LAN device under the PCI Express specification to provide dynamic packet transmission support. Simulation results show that the proposed mechanism and policy would reduce the system energy consumption substantially.

Contents
1 Introduction 4
2 System Architecture 7
2.1 PCI and PCI-Express Specifications . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2 Variable-Bitrate PCI-Express LAN Devices . . . . . . . . . . . . . . . . . . . . . 10
3 An Energy-Efficient Design for Variable-Bitrate PCI-E Devices 13
3.1 Problem Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.2 A Time-Slice-Based Transition Algorithm: The Basic Approach . . . . . . . . . . 15
3.3 A Revised Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4 Performance Evaluation 22
5 Conclusion and Future work 26

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