【摘要】 减少磁盘的存取时间是提高数据库性能的关键。本文讨论了 PostgreSQ L数据库顺序存取的特性,提出了一种 PostgreSQL 中顺序预取数据块的算法,预取的数据决数目可根据当前存取块之前的顺序存取情况作自适应调整。实验结果表明,该算法能有效地提高磁盘决的平均存取速度。更多还原

【Abstract】 Access speed of disk is the key to database performance.In this paper,after discussing a characteristic of se- quential access in PostgreSQL,an algorithm is proposed which can selectively prefetch data blocks ahead of the point of reference.The number of blocks prefetched is chosen based on the observed number of sequential block references im- mediately preceding reference to the current block.Experimental results show the proposed algorithm can improve ac- tess speed effectively.更多还原