A LOAD BALANCING ALGORITHM FOR UNSTRUCTURED GRIDS
R. LOÖHNER, Ravi Ramamurti · International journal of computational fluid dynamics · 1995
We present a general, parallelizable, load balancing algorithm for unstructured grid-based problems that belong to the so-called diffusion class and employ a give-and-take concept among neighbouring subdo-mains. The algorithm is found to converge very quickly to almost perfect load balance while minimizing the surface-to-volume ratio of the domains. The algorithm can be used for problems whose cost grows nonlinearly with the number of elements, because it measures continuously the computational cost to be incurred for each subdomain. This is an advantage over the recursive bisection algorithms currently in use, which assume a linear relationship between the computational cost and the number of elements. The load balancing algorithm is applied in conjunction with parallel heat transfer and parallel incompressible flow solvers for the solution of 2-D and 3-D problems, employing several hundred processors on a MIMD machine.