Research On Performance And Infrastructure Of File System Of NAND Flash

Recently, Flash memory was applied widely for its good characters, such as non-volatile, low-power consume, high-speed access and small area. But it's not char device nor block device, its special physical character bans its application in traditional file systems. Its character includes limited erase-cycle of each erase block and rewriting after erasion. These two characters will both affect performance and life cycle of flash memory. Developing a file system for flash memory to improve its performance and prolong its life cycle, is the target of lots of scholars.We do lot of research on the evolvement of flash memory file system, find out three main problem almost every flash memory file system faced: garbage collection, wear leveling and bad block management, and we do quantitative analyse also. First, we introduce the characters of flash memory, flash memory file system and its infrastructure; then approach a novel wear leveling algorithm based on data exchange between high-frequent erased block and low-frequent erased block, effectively level erasion among flash memory and prolong its life cycle with proof of data out of experiments; and we research several flash memory file systems up to the minute, analyse its garbage recollection, wear leveling and bad-block management, do some quantitative analyse. At last, we give the summary and perspective in this field.