When using METIS to perform the mesh partitioning, decides which algorithm is used. By default, graph partitioning is used for 8 or more partitions, and rcb for fewer.
Recursive coordinate bisection partitioning.
Graph partitioning (called 'k-way' by METIS).
grid/mesh_partition.F90 : 356
call parse_variable(namespace, 'MeshPartition', default_method, method)