Abstract-The increasing capacity of NAND flash memory results in larger page size. Since the larger page requires longer access time, the performance of a flash translation layer (FTL) that stores its mapping table in flash pages is degraded. An economical FTL named SCFTL is proposed to avoid such issues caused by the larger page. In order to reduce spatial requirements, SCFTL employs a demand-based caching mechanism for the page mapping table. Unlike other FTLs, SCFTL facilitates two techniques for delicately exploiting the spatial locality and customizes the replacement algorithm for reducing cache miss penalty. The experiments show that the average overhead of SCFTL in terms of access time is only 6.89%; this overhead is 75.96% and 11.35% lower than the state-of-the-art FTLs. The average cache hit ratio of SCFTL is as high as 0.92 despite compact memory footprint. Because of the outstanding cache utilization, SCFTL still achieves high performance even though the page size is larger.

3DFTL is a demand-based flash translation layer (demand-based FTL) that can withstand caching data loss due to unexpected events such as power-loss. Its mapping table in the flash memory is designed with the capabilities of being instantaneously updated with zero additional write operations. Moreover, the average cache miss penalty of 3DFTL is also lower than previous demand-based FTLs. As a result, not only the mapping table of 3DFTL guarantees data consistency, but 3DFTL also shows 16.42% decrease in terms of the average system response time comparing with the DFTL.

No abstract