针对不同NAND闪存读写操作成本比例的不同,提出一种具有高效页面替换功能的EPRA算法。在内存中,每个受害者候选页被分成固定数量的闪存页面。EPRA给每个受害者候选页分配权重值,在选择与修改页面时对权重进行调节,从候选页中选择具有最小权重值的页面作为受害者页。EPRA算法把受害者页中分为热的闪存页和冷的闪存页,并把这些数据写到NAND闪存中不同空闲的块中。仿真实验结果表明,EPRA算法使用在不同种类的NAND闪存中时,性能优于现有的页面替换算法。
In allusion to different cost ratios of read-write operation for different NAND flash memories, an EPRA algorithm with efficient page replacement function is proposed in this paper. Each victim candidate page in the internal storage is divided into a fixed number of flash pages. EPRA assigns a weighted value to each victim candidate page, and adjusts the weighted values in the process of page selection and modification. The page with least weighted value is selected in the candidate page as a victim page. EPRA divides the dirty flash pages into the hot dirty flash memory pages and cold ones, and writes the data in the different blocks in NAND flash memory. The trace-driven simulation resultes show that the EPRA algorithm is superior to the existing page replacement algorithms when it is used in different kinds of NAND flash memories.