Hosted by the 2021 IEEE SERVICES Congress, the Cloud HPC Symposium explores all aspects of the growing synergy between Cloud computing and High Performance Computing. Featuring paper presentations and talks from experts around the world, the symposium provides a forum for leading researchers, practitioners, and visionaries to share their R&D findings, experiences, and visions of Cloud HPC. Session 4 includes talks by Kyle Chard (University of Chicago), Bruce D'Amora (IBM Research), and Ilkay Altintas (SDSC).