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arXiv · 0707.2991

Graphic-Card Cluster for Astrophysics (GraCCA) -- Performance Tests

Hsi-Yu Schive·Chia-Hung Chien·Shing-Kwong Wong·Yu-Chih Tsai·Tzihong Chiueh
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Abstract

In this paper, we describe the architecture and performance of the GraCCA system, a Graphic-Card Cluster for Astrophysics simulations. It consists of 16 nodes, with each node equipped with 2 modern graphic cards, the NVIDIA GeForce 8800 GTX. This computing cluster provides a theoretical performance of 16.2 TFLOPS. To demonstrate its performance in astrophysics computation, we have implemented a parallel direct N-body simulation program with shared time-step algorithm in this system. Our system achieves a measured performance of 7.1 TFLOPS and a parallel efficiency of 90% for simulating a globular cluster of 1024K particles. In comparing with the GRAPE-6A cluster at RIT (Rochester Institute of Technology), the GraCCA system achieves a more than twice higher measured speed and an even higher performance-per-dollar ratio. Moreover, our system can handle up to 320M particles and can serve as a general-purpose computing cluster for a wide range of astrophysics problems.

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Hsi-Yu Schive, Chia-Hung Chien, Shing-Kwong Wong, Yu-Chih Tsai, Tzihong Chiueh. 2008-01-20. Graphic-Card Cluster for Astrophysics (GraCCA) -- Performance Tests. https://doi.org/10.1016/j.newast.2007.12.005

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