A memory deduplication approach based on group in virtualized environments

The combination of cloud computing and visualization technology introduces a new pattern on resource allocation and utilization. Memory scanning deduplication techniques based on eliminating duplicated pages among virtual machines can promote the resource utilization, and decrease the total cost of ownership. However, the existing memory deduplication technologies lack the supporting of isolation and trustworthiness mechanism. This paper proposes a memory sharing mechanism based on user groups. This mechanism guarantees isolation between the different users on the same host. In addition, we designed a sampling hash algorithm to make the memory scanning process more efficient. We have implemented our approach in Linux by modifying the KSM scanning mechanism and splitting the global ksmd thread into per-group ksmds. The experiment results show the work can optimize the memory-intensive VMs, and efficiently accelerate the memory scanning process.