PORCE: An efficient power off recovery scheme for flash memory

Flash memory is now replacing hard disk in many embedded applications including cellular phones, digital cameras, car navigation systems, and so on. However, because flash memory has its own characteristics such as “erase-before-write” and wear-leveling, a software layer called FTL (flash translation layer) should be provided. However, most FTL algorithms did not include the power off recovery module though it is very important in portable devices. In this paper, we suggest an efficient power off recovery scheme for flash memory called PORCE (Power Off Recovery sChEme for flash memory). PORCE is tightly coupled to FTL operations and minimizes performance degradation during normal operations by storing recovery information as small as possible. Additionally, PORCE provides cost-based reclamation protocols which include the wear-leveling module. Our empirical study shows that PORCE is an efficient recovery protocol.