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Performance characteristics of a parallel treecode

R. Valdarnini
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Abstract

I describe here the performances of a parallel treecode with individual particle timesteps. The code is based on the Barnes-Hut algorithm and runs cosmological N-body simulations on parallel machines with a distributed memory architecture using the MPI message passing library. For a configuration with a constant number of particles per processor the scalability of the code has been tested up to P=32 processors. The average CPU time per processor necessary for solving the gravitational interactions is within $\sim 10 %$ of that expected from the ideal scaling relation. The load balancing efficiency is high ($\simgt90%$) if the processor domains are determined every large timestep according to a weighting scheme which takes into account the total particle computational load within the timestep.

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R. Valdarnini. 2002-12-11. Performance characteristics of a parallel treecode. https://arxiv.org/abs/astro-ph/0212256

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