A Synchronization Protocol of Multi-Controller Storage

為減少微處理器與I/O設備的效能差距，目前普遍利用多I/O設備以增進資料平行化處理。本論文提出一個雙版本搭配多顆粒的控制同步協定，協助多控制器與多I/O設備進行同步處理，並增進系統效能。其中，多顆粒控制概念利用磁碟陣列的階層式架構進行資料同步，以最佳化I/O處理速率，而雙版本的控制策略能有效縮短高優先權的I/O要求的反應時間。我們並設計實驗將此同步協定在各式系統設定下進行比較，實驗中包含控制器數目的分析，以及真實的trace在不同讀寫比例下之測量。The exploring of request parallelism for I/O systems has been a successful strategy in conquering the performance difference between microprocessors and I/O devices. In this paper, a two-version multi-granularity protocol is proposed to maximize the controller concurrency of storage systems and to improve the system performance. The concept of multi-granularity is explored for the considerations of the hierarchical structure of such systems in stripes, blocks, etc, for operations. Synchronization based on two versions of data is adopted to favor operations with high urgency. The proposed protocol is evaluated over realistic traces with different configurations, such as the number of controllers and different read/write-operation ratios.List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ivist of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vist of Algorithms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vihapter 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1hapter 2 System Model and Problem Definition . . . . . . . . . . . . . . . . 3.1 System Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 Problem Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4hapter 3 A Synchronization Protocol . . . . . . . . . . . . . . . . . . . . . . 7.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2 The D2VMGT Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . 7hapter 4 Performance Evalution . . . . . . . . . . . . . . . . . . . . . . . . 13.1 Data Sets and Experiment Environment . . . . . . . . . . . . . . . . . . 13.2 Experiment Result . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14hapter 5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15ibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16eferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1