SearcharxivSearch

arXiv subjects

R. Maenner

Publications and source records attributed to R. Maenner.

2 recordsLinked to original sources

Collisional Stellar Dynamics, Gas Dynamics and Special Purpose Computing

Challenging stellar dynamical problems, such as the study of gravothermal oscillations in star clusters, have in the past initiated the very successful building of GRAPE special purpose computers. It is discussed, that present day tasks such as the formation and evolution of galactic nuclei with one or more massive black holes and the coupled stellar and gas dynamical processes in the formation of nuclei and star clusters, demand a new kind of hybrid architecture, using both GRAPE and a reconfigurable logics board called RACE. For such a system we have developed first implementations and floating point performance studies in the case of the SPH algorithm (smoothed particle hydrodynamics), which will be of great advantage for SPH modelling and also for direct $N$-body simulations using the more efficient Ahmad-Cohen neighbour schemes.

astro-ph

AHA-GRAPE: Adaptive Hydrodynamic Architecture - GRAvity PipE

In astrophysics numerical star cluster simulations and hydrodynamical methods like SPH require computational performance in the petaflop range. The GRAPE family of ASIC-based accelerators improves the cost-performance ratio compared to general purpose parallel computers, however with limited flexibility. The AHA-GRAPE architecture adds a reconfigurable FPGA-processor to accelerate the SPH computation. The basic equations of the algorithm consist of three parts each scaling with the order of O(N), O(N*Nn), and O(N**2) respectively, where N is in the range of 10**4 to 10**7 and Nn approximately 50. These equations can profitably be distributed across a host workstation, an FPGA processor, and a GRAPE subsystem. With the new ATLANTIS FPGA processor we expect a scalable SPH performance of 1.5 Gflops per board. The first prototype AHA-GRAPE system will be available in mid-2000. This 3-layered system will deliver an increase in performance by a factor of 10 as compared to a pure GRAPE solution.

astro-ph