Page Weight-Based Buffer Replacement Algorithm for Flash-Based Databases

摘要

With the development of flash memory technology and the increase of flash memory capacity, the flash memory storage is widely used, which brings opportunities and challenges to flash-based database management. The traditional buffer replacement algorithm for disk-oriented database fails to make full use of flash memory as a result of different read-write ways and read-write properties for flash memory and disk. This paper proposes the buffer replacement algorithm for flash-based database based on page weight called DPW-LRU. Based on the data page access frequency, the algorithm divides the buffer into hot list and cold list, and wherein, the former is used to store data pages accessed over two times, while the latter is used to store those accessed for once; at the same time, the dirty page is assigned weight to evict the low weight page preferentially. The experimental results show that the DPW-LRU algorithm is effective and feasible because it ensures hit ratio while reducing I/O access overhead.