Cost-Effective HPC: The Community or the Cloud?

The increasing availability of commercial cloud computing resources in recent years has caught the attention of the high-performance computing (HPC) and scientific computing community. Many researchers have subsequently examined the relative computational performance of commercially available cloud computing offerings across a number of HPC application bench-marks and scientific workflows, but the analogous cost comparisons-i.e., comparisons between the cost of doing scientific computation in traditional HPC environments vs. cloud computing environments-are less frequently discussed and are difficult to make in meaning-ful ways. Such comparisons are of interest to traditional HPC resource providers as well as to members of the scientific research community who need access to HPC resources on a routine basis. This paper is a case study of costs incurred by faculty end-users of Purdue University´s HPC “community cluster” program. We develop and present a per node-hour cloud computing equivalent cost that is based upon actual usage patterns of the community cluster participants and is suitable for direct comparison to hourly costs charged by one commercial cloud computing provider. We find that the majority of community cluster participants incur substantially lower out-of-pocket costs in this community cluster program than in purchasing cloud computing HPC products.