  The gravitational many-body problem is a problem concerning the movement of
bodies, which are interacting through gravity. However, solving the
gravitational many-body problem with a CPU takes a lot of time due to O(N^2)
computational complexity. In this paper, we show how to speed-up the
gravitational many-body problem by using GPU. After extensive optimizations,
the peak performance obtained so far is about 1 Tflops.
