关键词: 并行文件系统, Lustre, 细粒度, 输入/输出（I/O）

Abstract: Performance of coarse-grained I/O is good in parallel file system Lustre, performance of fine-grained I/O is relatively low compared with coarse-grained I/O, so performance optimization of fine-grained I/O is the key problem to improve I/O performance of overall system. On the research and analysis of Lustre I/O mode, fine-grained I/O service process and page replacement algorithm etc, it puts forward fine-grained priority FGF-LRU algorithm. It maximizes to retain fine-grained I/O pages in page cache of OST terminal and client terminal, reduces the page sinking speed caused by fine-grained I/O, extends time when fine-grained I/O page is in memory, thereby reduces the times of disk accesses and reduces disk access cost. It verifies the effectiveness of FGF-LRU algorithm based on comparison and analysis of the test data. It improves performance of fine-grained I/O without affecting performance of coarse-grained I/O, and ultimately improves I/O performance of the overall system.

Key words: parallel file system, Lustre, fine-grained, Input/Output（I/O）