Abstract: How to provide a stable and efficient file I/O performance for the upper application and computing,is the performance research hotspot oriented to distributed file system．This paper analyzed the mechanism in the design of the distributed file system on the common features,presented a general-purpose file prefetching heuristic module,and selected HDFS platform system to implement．The heuristic file prefetching module services the upper application and accomplishes the implementation in the internal of distributed file system,using the method of establishing prefetching thread pool within the file system,and the data not block as prefetching unit．This idea has certain universality,and is suitable for a variety of distributed file systems．Experimental results show that the heuristic file prefetching method can enhance the distributed file system I/O performance effectively．

Key words: Distributed file system,File prefetching,Heuristic,HDFS