PA-LIRS: An Adaptive Page Replacement Algorithm for NAND Flash Memory

Abstract

NAND flash memory is increasingly widely used as a storage medium due to its compact size, high reliability, low-power consumption, and high I/O speed. It is important to select a powerful and intelligent page replacement algorithm for NAND flash-based storage systems. However, the features of NAND flash, such as the asymmetric I/O costs and limited erasure lifetime, are not fully taken into account by traditional strategies. In order to address these existing shortcomings, this paper suggests a new page replacement algorithm, called probability-based adjustable algorithm onlow inter-reference recency set (PA-LIRS). PA-LIRS completely exploits the “recency” and “frequency” information simultaneously to make a replacement decision. PA-LIRS gives a greater probability to clean pages and a smaller probability to dirty pages when evict selection happens. In addition, this proposed algorithm dynamically adjusts the parameter based on the workload pattern to further improve the I/O performance of NAND flash memory. Through a series of comparative experiments on various types of synthetic traces, the results show that PA-LIRS outperforms the previous studies in most cases.