Analyzing Unikernel Support for HPC: Experimental Study of OpenMP.

Unikernels are single-application operating systems designed to run as virtual machines. They are popular in the cloud domain and are considered as a good alternative to containers due to the benefits they provide in terms of performance, low resource consumption, and security. This paper investigates the use of unikernels as a platform for HPC applications. The performance and stability of two unikernel platforms (HermitCore and HermiTux) are experimentally evaluated over standard representative HPC OpenMP benchmarks. We observe that unikernels remarkably reduce the overhead due to system calls, leading to a significant speedup (up to 77%) in system-bound applications. For applications that are not system-intensive, there are a few performance differences between the unikernel and the vanilla Linux execution. It should be remarked that modern unikernel projects are not yet fully mature, and exhibit stability issues running some OpenMP benchmarks.