Parallelization, Spatial Decomposition and Load Balancing of a Single Tree Level Forest Dynamics Simulator

Abstract

SPATE-HPC is a single tree level forest dynamics simulator capable of simulating very large forest areas. The size and shape of the simulation area as well as the number of trees are only restricted by the amount of memory available and subareas can be used for a tighter specification of the simulation.

In this article we describe the parallelization of SPATE-HPC and its major computational challenges. We describe the domain decomposition methods and the load balancing strategy we have used to ensure good performance and scalability of huge simulations. We also describe how we have verified the correctness of the parallel implementation. Additionally we present performance measurement results for the simulator by running a fixed 32,300 ha simulation on 32-2,048 processors and a simulation with 1,000 ha/core on 32-2,048 cores. The results show that it is possible to simulate a forest area of more than 1,000,000 ha with several billion trees.  MCFNS 2(1):30-40.