Minimizing CMT Miss Penalty in Selective Page-level Address Mapping Table

초록

Flash Translation Layer (FTL) performs virtual-to-physical address translations and hides the erase-before-write characteristics of Flash. Pure page mapped FTL, which maintains page-level address mappings, is known as the most efficient FTL. However, its huge SRAM requirement to load the entire mapping table limited adoption of its use. In order to reduce SRAM space utilization while maintaining comparable performance, we can selectively cache page-level address mappings into a small SRAM. However, the performance of this approach is limited by miss ratio of cached mapping table (CMT) on SRAM. In this paper, we propose a replica approach of the page-mapped FTL on flash, called Replica to minimize the performance penalty of CMT miss.