A Study on I/O Performance in Highly Consolidated Container-Based Virtualized Environment on OverlayFS with Optimized Synchronization

Virtualization has been utilized for a variety of purposes, such as server consolidation for saving many things like power consumption. A highly consolidated virtualized environment, in which many containers run simultaneously on a physical computer, can save these things remarkably. However, this environment may suffer from the large overhead of virtual machines and guest operating systems. In a virtualization technology field, Docker is attracting attention as a virtualization method without a large overhead. This is container-based virtualization and does not invoke the virtual machine and guest operating system. Our previous paper showed that Docker could not provide enough performance in I/O processing. The recent Docker is solving this performance issue by adopting OverlayFS, which causes less overhead. However, this filesystem has a performance problem on copy- up. We then proposed a method for solving this problem. In this paper, we demonstrate that our solving method can improve the container I/O performance also in a highly consolidated environment.