Scalable Ray Tracing Using the Distributed FrameBuffer

Will Usher, Ingo Wald, Jefferson Amstutz, Johannes Günther, Carson Brownlee, and Valerio Pascucci

In Computer Graphics Forum (Proceedings of EuroVis), 2019.

Fig. 1: Large-scale interactive visualization using the Distributed FrameBuffer. Top left: Image-parallel rendering of two transparent isosurfaces from the Richtmyer-Meshkov (516M triangles), 8FPS with a 2048^2 framebuffer using 16 Stampede2 Intel Xeon Platinum 8160 SKX nodes. Top right: Data-parallel rendering of the Cosmic Web (29B transparent spheres), 2FPS at 2048^2 using 128 Theta Intel Xeon Phi Knight’s Landing (KNL) nodes. Bottom: Data-parallel rendering of the 951GB DNS volume combined with a transparent isosurface (4.35B triangles), 5FPS at 4096x1024 using 64 Stampede2 Intel Xeon Phi KNL nodes.


Image- and data-parallel rendering across multiple nodes on high-performance computing systems is widely used in visualization to provide higher frame rates, support large data sets, and render data in situ. Specifically for in situ visualization, reducing bottlenecks incurred by the visualization and compositing is of key concern to reduce the overall simulation runtime. Moreover, prior algorithms have been designed to support either image- or data-parallel rendering and impose restrictions on the data distribution, requiring different implementations for each configuration. In this paper, we introduce the Distributed FrameBuffer, an asynchronous image-processing framework for multi-node rendering. We demonstrate that our approach achieves performance superior to the state of the art for common use cases, while providing the flexibility to support a wide range of parallel rendering algorithms and data distributions. By building on this framework, we extend the open-source ray tracing library OSPRay with a data-distributed API, enabling its use in data-distributed and in situ visualization applications.


  journal = {Computer Graphics Forum},
  title = {{Scalable Ray Tracing Using the Distributed FrameBuffer}},
  author = {Usher, Will and Wald, Ingo and Amstutz, Jefferson and
      Günther, Johannes and Brownlee, Carson and Pascucci, Valerio},
  year = {2019},
  publisher = {The Eurographics Association and John Wiley & Sons Ltd.},
  ISSN = {1467-8659},
  DOI = {10.1111/cgf.13702}