VisIt-OSPRay: Toward an Exascale Volume Visualization System.

Large-scale simulations can easily produce data in excess of what can be efficiently visualized using production visualization software, making it challenging for scientists to gain insights from the results of these simulations. This trend is expected to grow with exascale. To meet this challenge, and run on the highly parallel hardware being deployed on HPC system, rendering systems in production visualization software must be redesigned to perform well at these new scales and levels of parallelism. In this work, we present VisIt-OSPRay, a high-performance, scalable, hybrid-parallel rendering system in VisIt, using OSPRay and IceT, coupled with PIDX for scalable I/O. We examine the scalability and memory efficiency of this system and investigate further areas for improvement to prepare VisIt for upcoming exascale workloads.