一种高效率访问NAND数据的方法

A Method for Highly Efficient Access to NAND Data

针对NAND闪存的擦写特点,提出了一种基于内存的数据缓存机制访问NAND数据的方法。该方法以NAND块大小的整数倍创建缓存,并采用了"缓存块使用率"的缓存替换机制。使用该方法不仅大大提高了缓存的有效命中率,而且能大幅提高NAND的读写速度。提出的数据缓存机制,对于NAND的写操作,不需要每次都写入NAND,也能有效减少对NAND的擦写次数,不但可以降低坏块产生的几率,而且可以有效的延长NAND使用的寿命。

For the erase-write characteristic of NAND flash memory, a memory-based method for accessing to NAND data with data caching mechanism is proposed. This method creates cache by integral multiple of NANDblock size, and uses the buffer replacement mechanism based on ＂buffer block utilization ratio＂. This method could greatly enhance effective hit rate of cache memory, and improve the read-write speed of NAND. For write-operation of NAND, the proposed data caching mechanism need not write in NAND every time, and could effectively reduce the erase-write times on NAND. This mechanism could decrease the probability for generating bad block, and prolong effectively the life of NAND.