快閃記憶體檔案系統、即時壓縮模型及緩衝區架構管理之研究

快閃記憶體具體積小、重量輕、非揮發性、耐震及低功耗等特性，因此成為移動式裝置中必備的儲存裝置之一。雖然快閃記體廣泛的使用於各移動式裝置中，但快閃記憶體不能原處更新資料、抹除/寫入單位次數有限及容量不及傳統式硬碟，因此本論文探討快閃記憶體的檔案管理機制、即時壓縮方法架構與緩衝區管理架構。在管理系統中，由於快閃記憶體特性所致傳統式檔案管理系統不合使用，所以本論文在考量效能及可靠度條件下提出可適度管理方法，並於嵌入式平台與公開式檔案管理系統作效能、可靠度及功耗評估；再者，本論文提出快閃記憶體及時性壓縮架構配合X-RL硬體壓縮演算法，連續配置策略可避免壓縮所產生資料頁內部破碎，雙緩衝區的設計可使得存取達到及時性效果；進一步，由於緩衝器允許資料原處更新並且存取速度以及功率消耗都優於快閃記體，緩衝區管理的設計將可有效減少快閃記體儲存裝置功耗，所以本論文針對快閃記憶體特性設計一緩衝區架構，並且在管理策略中針對時間及空間拘限性提出根據檔案存取狀況的適應管理方法。

關鍵字

快閃記憶體；檔案系統；即時壓縮管理架構；緩衝區管理架構；灰色理論

並列摘要

Flash memory is essential storage for mobile device because it is small, lightweight, non-volatility, vibration-resistant and low energy consumption. Although Flash memory is used extensively in mobile devices, its characteristic makes that the data cannot be updated in situ, the number of erase operations is limited, and the capacity is less than traditional HD. Therefore, this dissertation discusses file system, real-time compression architecture, and buffer management for flash memory. In management policy, flash memory cannot be managed using traditional file systems as its characteristic. So, this dissertation proposes an adaptive management mechanism and evaluates performance, reliability, and energy consumption. Moreover, we propose a mechanism that uses a packing agent and a ping-pong buffer to cooperate with the X-match and run-length compression/decompression algorithm to create a real-time compression layer. It can avoid internal fragmentation space and make real-time performance. Further, the energy consumption and latency of the buffer are less than those for flash memory, and the data of the buffer can be updated in situ. So, we propose the buffer architecture tailored to the properties of flash memory and an adaptive policy according to the recent file state for effectively reducing the energy consumption.

並列關鍵字

Flash memory ； File system ； Real-time compression ； Buffer management ； Grey system.

參考文獻

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快閃記憶體檔案系統、即時壓縮模型及緩衝區架構管理之研究

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