Hybrid-LRU Caching Scheme for PDRAM Hybrid Memory Architecture in Cloud Computing

Abstract

This in recent years, the mixed memory (PDRAM) which is consisted of the phase-change memory (PRAM) and the conventional memory (DRAM) has drawn a lot of attention from both industry and academia. It is a promising alternative to replace the traditional memory architecture. PDRAM has good characteristics as large capacity, good stability and non-volatile, while PRAM has disadvantages of a limited life and large access latency. Traditional policies are not sufficient to be directly applied to the PDRAM memory architecture. They cannot adapt to the new features of the hybrid architecture because of their undifferentiated operation, extensive use of PRAM can cause performance degradation and shorten the life of PDRAM memory. This paper proposed Hybrid-LRU caching scheme to address these problems. Our scheme mainly uses the cache consistency address resolution mode to distinguish between different physical mediums in PDRAM, and then take different actions depending on different physical mediums. We have taken a variety of tradition policies like LRU, FIFO, RANDOM, CFLRU to make experimental comparisons. The experimental results have shown that our scheme can reduce the PRAM utilization rate of 11.8% and improve the performance by 4.6%, energy consumption of write and read operation can be reduced up to 88.2%.