用以調校NAND快閃固態硬碟中垃圾回收機制之數學模型

Abstract

快閃固態硬碟已然成為電腦中非常重要的元件，然而，其中的垃圾回收機制依舊是提升固態硬碟效能之一大瓶頸。在本篇論文中，我們將提出一個數學模型來預測垃圾回收機制中，各參數的設定將對效能產生多少衝擊，其中包括實行垃圾回收機制的時間點、一次要回收多少區塊、使用者的存取習慣等等，最後將數學模型預測之結果與模擬實驗所跑出來的結果進行比較，並分析各個參數中，哪些對效能的影響是巨大的。

NAND flash-based SSD has become an important component of the computer. However, the problem of garbage collection for it remains a bottleneck. In this thesis, a mathematical model to predict the impact of each parameter on the performance of garbage collection will be proposed. These parameters include the temporal locality from access pattern, the ratio of logical storage space to physical storage space, etc. The results of mathematical model will be compared with those of simulations. Finally, how much impact each parameter has on the performance of garbage collection will be analyzed by simulation results.