[petsc-users] Why am I not getting the parallel running?

[Jed Brown]

On Mon, 19 Apr 2010 12:31:04 -0500, Matthew Knepley <knepley at gmail.com> wrote:
> On Mon, Apr 19, 2010 at 12:28 PM, Li, Zhisong (lizs) <lizs at mail.uc.edu>wrote:
> 
> >   Hi,
> >
> > I think this is a beginner's question, but still hope someone can help me
> > out.
> >
> > I've tried to run some PETSc examples and my own simple PETSc codes on my
> > office's cluster as well as on Ohio Supercomputer Center's machine. At first
> > I found no speedup for parallel processing and later I noticed by checking
> > the rank that actually each node is doing the same sequential processing.
> > I'm sure the codes are parallel codes (such as ex19.c in SNES and ex7.c in
> > TS tutorial codes). Is there anything I am missing in the installation or
> > the run command such as"mpiexec -n 3 ex7"? How can I realize a parallel
> > running?
> >
> 
> The mpiexec in your path is not the one you configured with. What
> MPI is begin used?

Does make test run successfully?  If so, then

  $ cd src/snes/examples/tutorials && make -n runex5

will tell you which mpiexec PETSc is using.

Jed