OEBS:一种闪存磨损均衡算法  

Flash Wear Leveling Algorithm-OEBS

作　　者：刘洋[1] 陆冠群[1] 陈章龙[1] 涂时亮[1] 

机构地区：[1]复旦大学计算机科学与工程系,上海200433

出　　处：《小型微型计算机系统》2009年第12期2489-2492,共4页Journal of Chinese Computer Systems

摘　　要：闪存诞生以来得到了广泛应用,它的特性包括:块擦除次数有限和擦除后重写.这两个特性都会影响闪存的使用寿命.针对这一问题,本文提出并实现了一种新颖的磨损均衡算法-OEBS(Outstanding Erase Block Set)-显性擦除块集.该方法通过高低频数据互换,有效均衡了擦除分布;使用显性擦除块集保护显性擦除块,避免了互换颠簸;将显性擦除块集和非显性擦除块集分开管理,提高了效率.模拟实验数据结合量化了的使用寿命延长度,表明数据块的擦除分布均匀,效率较高,有效延长了闪存的使用寿命.Flash memory is widely used after its birth, but it still staggers on the way, the main reason is that it has hardware shortcomings, the block erase counts are limited and over-writing must follow erasing. These two characters both affect flash＇s life cycle. To solve this problem, this paper presents the design and implementation of a novel wear leveling algorithm, OEBS （ Outstanding Erase Block Set）. Data exchange between high-frequent erased block and low-frequent erased block is adopted to even the erasure distribution; OEBs are protected in OEBS and exchange-swirl is avoided; OEBS and NOEBS （ Non-outstanding Erase Block Set ） are managed respectively to get better efficiency. The result comes out of simulation tests shows more even distribution, better efficiency and longer life cycle with a formula to measure the DFLCP（ Degree of Flash Life Cycle Prolongation）.

关 键 词：闪存 磨损均衡 显性擦除块集 使用寿命延长度 互换颠簸 高效 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]