Cache调度策略在磁盘操作中占着举足轻重的地位,调度策略设计的好坏直接影响着磁盘I/O性能。磁盘上非连续的扇区的存取需要多个I/O来完成。当数据读入Cache或Cache腾空时,磁盘旋转等待时间是不可避免的。本文分析了磁盘中常用的Cache调度算法存在的不足,提出了一种新的调度策略,一次I/O即可完成非连续扇区的存取操作,把旋转延迟缩至最小程度,在某些情况下可达到零延迟。 Cache scheduling strategy plays a decisive role in disk operation. The design of scheduling strategy directly affects disk I / O performance. Discontinuous sector access on disk requires multiple I / O to complete. When data is read into the cache or cache is emptied, disk rotation latency is inevitable. This paper analyzes the shortcomings of Cache scheduling algorithm commonly used in the disk, proposes a new scheduling strategy, an I / O can be completed non-sequential sector access operation, the rotation delay is reduced to a minimum, in some Zero delay can be achieved in the case.