Abstract: HDFS has a significant advantage on storing the massive files,however,its storage architecture which has onlyone NameNode will result in the decrease of performance when HDFS is used to store massive files which is mainly composed by small files .A solution based on the idea of that small files were merged into large files was proposed.Meanwhile,the mapping relationship from small files to merging files was established and stored into HBase.Finally,we provided a LRU based prefetching mechanism to improve the reading speed.The experiments show that the proposed method can improve the overall performance of HDFS with the large amounts of small files.

Key words: HDFS,Massive files,Merging,Mapping,LRU,Prefetch mechanism