HPC Consortium: Sun Visualization System at the LCN
By Josh Simons on Jul 01, 2007
The LCN is a collaboration between University College London and Imperial College London, focusing on nanoCAD and nano-fabrication, among other areas, and exploring both biological and non-biological fabrication techniques for building nano-scale structures.
The Center's visualization requirements include the ability to visualize very large data sets and to allow intuitive access to these capabilities for both business decision makers and lab researchers. Workstations were considered and rejected because they cannot offer the computing power needed to handle the large data sets used at the Center.
LCN has been working in collaboration with Sun to create a visualization system based on Sun's Scalable Visualization Software. Their system uses a large, active stereo screen, a Sun Fire x4600 as the application engine, a Sun Fire x4500 ("Thumper") node for storage, and two headless Sun Ultra 40 systems as rendering engines. Voltaire InfiniBand is used as the system interconnect.
From a user's perspective, one logs into the x4600 and runs an application which then locally generates the 3D stereo renderings they see on the large display. In fact, what is actually happening is a bit more complicated, though it does not interfere with the intuitive user experience. The application is indeed running on the X4600, taking advantage of the available large memory and processing power of this SMP node. However, the graphical rendering is actually performed on the two Ultra 40 machines which each then send pixel streams to the display with each Ultra 40 responsible for computing the image on one half of the display surface.
This feat is accomplished through use of Sun's Scalable Visualization Software which transparently interposes itself on the application's OpenGL calls and routes the graphics requests to the Ultra 40s over the InfiniBand link.
While LCN currently uses two graphics workstations there is no reason in principle that they could not extend the approach to use four workstations, each responsible for one quarter of the display screen.
As the collaboration with Sun continues, LCN is interested in exploring the use of Sun Grid Engine to allow compute nodes beyond their single x4600 to be used as part of this system. In addition, they are interested in exporting graphics output to desktops and Sunrays so as to more broadly share the visualization system's capabilities within LCN. To do this, they will also use Sun's Shared Visualization Software.