Application-Aware Swapping for Mobile Systems

Abstract

There has been a constant demand for memory in modern mobile systems to provide users with better experience. Swapping is one of the cost-effective software solutions to provide extra usable memory by reclaiming inactive pages and improving memory utilization. However, swapping has not been actively adopted to mobile systems since it incurs a significant amount of I/O, which in fact impairs system performance as well as user experience. In this paper, we propose a novel scheme to properly harness the swapping to mobile systems. We identify that a vast amount of I/O for swapping comes from the conflict of the traditional page-level approach of the swapping and the process-level memory management scheme tailored to mobile systems. Moreover, we find out that the current victim page selection policy is not effective due to the process-level policy. To address these problems, we revise the victim selection policy to resolve the conflict and to selectively perform swapping according to the efficacy of swapping. Evaluation using a running prototype with realistic workloads indicates that the propose scheme effectively reduces the paging traffic, thereby improving user experience as well as energy consumption.