Scotch — Software package and libraries for sequential and parallel graph partitioning, static mapping, sparse matrix block ordering, and sequential mesh and hypergraph partitioning.
METIS – A set of serial programs for partitioning graphs, partitioning finite element meshes, and producing fill reducing orderings for sparse matrices.
ParMETIS – An MPI-based parallel library that implements a variety of algorithms for partitioning unstructured graphs, meshes, and for computing fill-reducing orderings of sparse matrices.
PETSc – Portable, Extensible Toolkit for Scientific Computation: widely used parallel numerical software library for partial differential equations and sparse matrix computations.