分析flash 文件系统的损耗均衡问题,指出损耗均衡的触发条件对系统I/O 性能的影响。在最新UBIFS 文件系统上运行测试程序, 结果证明在不同损耗均衡触发条件下,系统I/O 性能的最大差距超过20%。针对现有损耗均衡算法的不足提出一种改进的自适应算法。 关键词:损耗均衡;垃圾回收;系统I/O 性能;flash 文件系统 Impact of UBIFS Wear-leveling on System I/O Performance HAN Chun-xiao, CHEN Xiang-lan, LI Xi, GONG Yu-chang (Department of Computer Science and Technology, University of Science and Technology of China, Hefei 230027) 【Abstract】This paper analyzes the problem of file system wear-leveling, and points out that the wear-leveling trigger condition will impact system I/O performance. Benchmark is performed on a latest flash file system——UBIFS, and the results show that system I/O performances vary by 20% under different trigger threshold. Aiming at the shortcoming of existing wear-leveling algorithm, it proposes an improved self-adapting algorithm. 【Key words】wear-leveling; garbage-collection; system I/O performance; flash FS