近年來，NAND型快閃記憶體由於非揮發性、防震及低功耗的特性，廣泛地應用在嵌入式裝置、攜帶式裝置及高性能的儲存產品。但NAND型快閃記憶體的壽命一值是大家所關注的議題，尤其是NAND閃存的特點，在寫入前擦除。在垃圾收集時，如果被挑到要抹除的區塊裡面有有效頁面時，必須先將有效頁面搬移至空的區塊才可以進行抹除。在本文中，我們試圖在兩個部份提高NAND型快閃記憶體的壽命。首先，我們透過冷熱辨識減少有效頁面的搬移數量，第二，我們提高了在快取中的命中率。實驗結果表示我們的方法在FAT32的資料串流下快取命中率提升了7.18倍，而有效頁面搬移量減少了4.56倍。

In recent years, flash memory has been widely used in embedded systems, portable devices, and high-performance storage products due to its non-volatility, shock resistance, low power consumption, and high performance natures. Lifetime of NAND flash memory is a concern issue. Especially the characteristic of NAND flash memory, erase before write. In the garbage collection, copy the valid page to free block if any valid page in victim block. In this paper, we try to enhance lifetime of NAND flash memory in two parts. First, we reduce the number of valid page copied by hot/cold identify. Second, We improve the hit ratio in cache. The experiment results show that the hit ratio can be improved by 718%, and the number of valid page copied can be reduce by 456% in FAT32 with our proposed management scheme.

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