An efficient file-aware garbage collection algorithm for NAND flash-based consumer electronics

Abstract

The use of NAND flash memory is increasing in consumer electronics. Because an out-of-place update scheme is used to address the erase-before-write hardware constraint in NAND flash memory, a garbage collection algorithm should be designed into the flash translation layer (FTL) or the flashspecific file system to reclaim garbage pages and obtain free space. In this paper, an efficient file-aware garbage collection algorithm, called FaGC, is proposed for NAND flash memory systems in consumer electronics. The purpose of the proposed algorithm is to reduce garbage collection overhead and improve wear leveling in NAND flash memory systems. The experimental results show that the proposed algorithm outperforms existing garbage collection algorithms in terms of the number of copy operations, the number of erase operations, and the degree of wear leveling. Additionally, with limited cost, a desired degree of wear leveling can be achieved using a predesignated value, which is advantageous for NAND flash memory systems in consumer electronic devices.