Partition Compression Flash Translation Layer Based on Data Separation

Flash translation layers play an important role in determining the storage performance and lifetime of NAND flash-based electronics devices. And file system designs are undergoing rapid evolution to exploit the potentials of flash memory. Although many compression Flash Translation Layer (FTLs) have been designed, there is serious overhead for the software compression or even hardware compression and decompression process which are inevitable. In this paper, we present a partition FTL which can distinguish the file system metadata and user data. After the division of the mapping table, we add transparent data compression to the user data part, a logical partition compression, called pcFTL, which reduces the amount of data written into NAND flash memory. In addition, no more decrease in (Solid state drive) SSD performance due to no filesystem metadata compression overhead. Transplanting compression on user data part, other than file system data part not only benefit disk performance but also save SDRAM space. pcFTL is one kind of filesystem suited FTL design.