关键词: 键值, 固态硬盘, 虚拟内存, 缓冲区

Abstract: Key-value in-memory databases have the characteristics of efficiency, usability and scalability. Because of the limits of the capacity of main memory, the applications dealing with large amount of data have to swap data between main memory and disks. While solid state disks (SSDs) have the high performance of random reads as a new storage medium, they can speed up random reads on virtual memory. To remedy the lower performance of random writes on SSDs, this paper proposes an optimization method of write buffer of SSD, which transforms several random writes to a sequential write, and designs a garbage collection policy of SSD, which transforms several random writes to a sequential read and a sequential write, to improve the spatial utilization of key-value in-memory database. Finally, an SSD-based virtual memory implementation is proposed to realize high performance of key-value main memory data-bases, and the improvement which is at most 40%, is confirmed by changing the source code of Redis in experiment.

Key words: key-value, solid state disk (SSD), virtual memory, buffer