Implicit Programming: A Fast Programming Strategy for nand Flash Memory Storage Systems Adopting Redundancy Methods

Abstract

The aggressive shrinking of process geometry and an increase in the number of bits stored in each memory cell of NAND flash memory inevitably degrade the reliability of NAND flash. Redundancy methods have been widely adopted to enhance the reliability of the system data in NAND flash memory. However, the redundancy process will induce extra program operations which will sharply degrade the I/O performance of the system. This letter presents implicit programming strategy, a fast redundancy strategy for NAND flash memory storage systems adopting redundancy methods. Our technique for the first time exploits the property of the copyback operation and combines the normal program operation and copyback program operation to reduce the I/O performance overhead induced by the redundancy process. We have implemented implicit programming on a real hardware platform. The experimental results shoChang-DAC09w that by combining with implicit programming, one redundancy scheme (Meta-Cure) can reduce up to 27.24% of the I/O performance overhead.