Android存储系统中NAND闪存性能的改进

Improvements on the Performance of NAND Flash in Android Memory System

摘要:

针对Android存储系统在闪存管理上存在较差的磨损均衡效果和较高的垃圾回收额外开销的缺陷,引入冷热数据分离策略,将文件按照不同热度写入对应热度的物理存储单元,同时改进垃圾回收策略,以达到良好的磨损均衡效果并减少垃圾回收额外开销。基于Android平台的实验结果表明,改进后的策略在有效减少NAND闪存垃圾回收额外开销的同时,还能有效改善其磨损均衡效果。

Abstract:

To solve the problem of Android memory system in wear leveling and garbage collection, the policy of cold/hot data separation is adopted to write files to the corresponding physical memory unit according to different heat. Then, the policy of garbage collection is improved to get better performance of wear leveling and garbage collection. Experimental results based on Android platform show that the garbage collection overhead for NAND flash is reduced and the degree of wear leveling for NAND flash is improved in Android memory system.