SAW: System-Assisted Wear Leveling on the Write Endurance of NAND Flash Devices

The write endurance of NAND flash memory adversely impacts the lifetime of flash devices. A flash cell is likely to wear out after undergoing excessive Program/Erase (P/E) flips. Wear leveling is hence employed to spread erase operations as evenly as possible. It is traditionally conducted by the Flash Translation Layer (FTL), a management firmware residing in flash devices. In this paper, the authors shall propose a novel wear leveling algorithm involving the Operating System (OS). They will show that their operating System-Assisted Wear leveling (SAW) algorithm can significantly improve the wear evenness.