We have a C++ FEM package with a set of different solvers. I want to add anther sparse iterative solver package along to the lis package. We use OpenMP but not MPI.

From what I found, trilinos might be the right package to use, but I find the start a little difficult. I guess one needs to decide for either Epetra or Tpetra, the later sound appealing as we also solve complex systems.

My question is, if Tpetra can be used with OpenMP only and completely without MPI (so not one rank but still a mpi compiler required).

I also do not understand “Epetra is mature, Tpetra is the future”. Does this indicate that one shall better start with Tpetra?