BlockSolve95 is a scalable parallel software library primarily intended for the
solution of sparse linear systems that arise from physical models, especially
problems involving multiple degrees of freedom at each node. For example, when
the finite element method is used to solve practical problems in structural
engineering, each node typically has two to five degrees of freedom;
BlockSolve95 is designed to take advantage of problems with this type of local
structure. BlockSolve95 is also reasonably efficient for problems that have
only one degree of freedom associated with each node, such as the three-
dimensional Poisson problem.

BlockSolve95 is general purpose; we do not require that the matrices have any
particular structure other than being sparse and being symmetric in structure
(but not necessarily in value).

WWW: http://www-unix.mcs.anl.gov/sumaa3d/BlockSolve/