Lightning-2: a high-performance display subsystem for PC clusters

ABSTRACT

Clusters of PCs are increasingly popular as cost-effective platforms for supercomputer-class applications. Given recent performance improvements in graphics accelerators, clusters are similarly attractive for demanding graphics applications. We describe the design and implementation of Lightning-2, a display subsystem for such a cluster. The system scales in both the number of rendering nodes and the number of displays supported, and allows any pixel data generated from any node to be dynamically mapped to any location on any display. A number of image-compositing functions are supported, including color-keying and depth-compositing. A distinguishing feature of the system is its platform independence: it connects to graphics accelerators via an industry-standard digital video port and requires no modifications to accelerator hardware or device drivers. As a result, rendering clusters that utilize Lightning-2 can be upgraded across multiple generations of graphics accelerators with little effort. We demonstrate a renderer that achieves 106 Mtri/s on an 8-node cluster using Lightning-2 to perform sort-last depth compositing.

REFERENCES

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS

Additional Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.4 Distributed Systems
          Subjects: Client/server

  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.1 Hardware architecture
          Subjects: Parallel processing
      I.3.2 Graphics Systems
          Subjects: Distributed/network graphics
      I.3.3 Picture/Image Generation
          Subjects: Bitmap and framebuffer operations

General Terms:
Design, Performance, Theory

Keywords:
graphics hardware, graphics systems, parallel computing, rendering hardware, rendering systems