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Are You Ready to FLY in the Universe ? A Multi-platform N-body Tree Code for Parallel Supercomputers

U. Becciani·V. Antonuccio-Delogu
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Abstract

The code we describe (FLY) is a newly written code (using the tree N-body method), for three-dimensional self-gravitating collisionless systems evolution. FLY is a fully parallel code based on the tree Barnes-Hut algorithm and periodical boundary conditions are implemented by means of the Ewald summation technique. FLY is based on the one-side communication paradigm to share data among the processors, that access to remote private data avoiding any kind of synchronism. The code was originally developed on CRAY T3E system using the logically SHared MEMory access routines (SHMEM) but it runs also on SGI ORIGIN systems and on IBM SP by using the Low-Level Application Programming Interface routines (LAPI). This new code reaches good performance in all systems where it has been well-tested. This performance allows us today to consider the code FLY among the most powerful parallel codes for tree N-body simulations. The FLY version 1.1 is freely available on http://www.ct.astro.it/fly/ and it will be maintained and upgraded with new releases.

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U. Becciani, V. Antonuccio-Delogu. 2001-01-10. Are You Ready to FLY in the Universe ? A Multi-platform N-body Tree Code for Parallel Supercomputers. https://doi.org/10.1016/s0010-4655(00)00253-8

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