Transparent Transition of a User-Level Service to Kernel-Level Functionality

While there are a number of user-level services that extend the functionality of operating systems, they suffer from difficulty of development and performance degradation. This paper proposes a novel methodology that enables the transparent transition from the development of a user-level service to kernel-level functionality. By employing the proposed methodology, 1) a new service is efficiently developed at the user level, and then 2) the developed service is implemented as the kernel-level functionality for better performance. We realized the methodology on the Unikernel Linux (UKL) as UKL maintains the existing system call interface for user-level programs.