[petsc-users] How to parallelize a linear system solver A*x=q in a scalar code

[Valerio Grazioso]

Dear All,
I have to parallelize an old fortran77-fortran90 cfd scalar code. Before starting from scratch, I decided to parallelize “just” the pressure solver (for instance a linear system solver A*x=q).
Because of the subroutines call tree, and in particular for the fact a lot of subroutines are doing some output,  it would be of great help if I could let just one process run trough the main, leaving all the others on hold (with an MPI_Barrier), just to the point where I create an MPI matrix (an MPI vectors as well) with MatCreate, and then resolve the “parallel” system. Is this plan feasible with petsc ? 

Thanks

Valerio Grazioso