一种针对时间局部性访问的固态硬盘缓存算法

A SSD Caching Algorithm for Temporal Locality Access

针对内存、固态硬盘、机械硬盘构成的混合存储系统中的时间局部性访问,提出了基于变化替换代价的动态缓存算法DRCC,该算法通过预约队列和最小代价优先队列实现数据的组织,同时两个队列分别进行数据的淘汰,充分解决了时间局部性访问的热点迁移所带来的缓存污染问题。将每小时平均IOPS、总平均IOPS作为评价指标,利用模拟数据将DRCC算法与多种主流缓存算法进行了测试对比。测试结果表明,与其他缓存算法相比,DRCC算法具有更高的读写效率。

The temporal locality access of hybrid storage system which is composed of RAM,SSD and RAID is concerned,the DRCC algorithm is proposed based on ohange replacement cost,which organizes data through order queue and minimum cost queue,and eliminates data in both two queues.DRCC algorithm can solve the problem of cache polluting caused by hot-spot chang⁃ing of temporal locality access.Taking hourly average IOPS and total average IOPS as evaluating indicator,the DRCC algorithm is compared with several mainstream caching algorithms via simulated data.The testing results show that the DRCC algorithm offers higher read-write efficiency than other caching algorithms.