Design and implementation of page sharing scheme between guests in virtualization environments

According to the development of virtualization technology and enhancement of hardware performance, there will be more and more guests on a host in virtualization environments. These guests use many common files and each file should be duplicated on each guest filesystem and memory. In order to eliminate these duplications of resources, many corporations and laboratories proposed several resource sharing schemes. However, there are some problems such as overhead and complexity. In this paper, in order to reduce such duplications, we propose a page sharing scheme optimized for executable files and libraries using shadow paging. Also, we validate our scheme with some evaluation results that show improvements in memory utilization and performance, through the implementation of the proposed scheme and experiments.