A-PLR: Accumulative backup of mapping information for power loss recovery

Abstract

In NAND flash memory based storage systems, a flash translation layer (FTL) is usually employed to hide shortcomings of NAND flash memory such as erase-before-write and asymmetric read/write response time. Although there are several types of FTLs according to the mapping granularity, it is a recent trend to use a page-level mapping FTL. There are two basic methods of power loss recovery (PLR) schemes for page-level mapping FTL: per-page-unit method and the map block-unit method; however, these methods have shortcomings in term of the recovery time and the mapping information management overhead, respectively. In order to overcome disadvantages of PLR, thus, we propose a novel PLR, named accumulative backup of mapping information for power loss recovery (A-PLR), which provides a stable data recovery performance without any management overhead.