Re: How is mpi-default-dev supposed to work?
Am Dienstag, den 23.03.2010, 13:16 +0100 schrieb Lucas Nussbaum:
> I'm not the mpi-defaults maintainer :-) Manuel? Adam?
Sorry for replying late!
mpi-defaults was supposed to be an interim solution and in an ideal
world gone already. I know it's not the best solution out there, but the
best we have at the moment.
To comment on the discussions you had: The problem Thibaut mentions only
exists on the platforms where both implementations exist and mpich2 is
installed later into a buildd chroot. Lucas, you're right with what you
said about the buildds but I'm not sure if we can (or should, for that
matter) rely on that. On platforms where Open MPI is not available,
there is no problem, as Open MPI never built on those anyway.
The easiest (and cleanest) solution seems to be to add mpicc.default and
friends (or whatever we call it) to mpi-defaults-dev, being symlinks to
the default mpicc on that platform. Those can be used by the packages
using only mpi-defaults-dev. The only downside I see right now it the
fact that we should fix all packages not using it also which has a
negative effect on the whole transition. On the other hand, we do not
need to; it won't break anything if the assumptions made are valid. (But
as said, we can't really rely to it.)
I could also increase the update-alternatives priority of Open MPI to
something higher than MPICH2. This should have no negative side effects
but does of course not fix the current problem. What do you think about
that? (Planning to upload some minor fixes to Open MPI anyway.)
Last, I recently changed the arch list in mpi-defaults to match that of
Open MPI on all platforms. There are some more platforms supported now,
and I hope this goes on. Just wanted to mention that, it does have
nothing to do with this really.