MFence: Defending Against Memory Access Interference in a Disaggregated Cloud Memory Platform

A VM-based disaggregated cloud memory platform (DCM) virtualizes the memory device of a remote server connected to a highspeed network as an expansion of local memory. DCM provides large memory to applications to increase throughput. However, DCM is not well-suited to managing fair memory usage between processes when they run concurrently in a VM. This is because DCM has no mechanism to provide independent memory space to each process. As a result, DCM does not guarantee fairness and performance to processes. Partitioning memory for each process is a way to solve this problem. However, in DCM, the host kernel running DCM cannot obtain the memory page information of a process (including memory page address and PID) running in the guest kernel. So it can not segregate memory pages according to the process. Therefore, this paper proposes an efficient method for the host kernel to obtain the memory page information to partition the memory for each process in DCM, called MFence. The MFence was evaluated using two Linux servers connected by a 100 Gbps IB network. Extensive evaluation has confirmed that MFence ideally provides memory partitioning to provide fairness between processes and improve overall performance.