Re: PetSc

[Junichi Uekawa <dancer@netfort.gr.jp>]

In 12 Jan 2001 11:23:53 -0500 Camm Maguire <camm@enhanced.com> cum veritate scripsit :

> My understanding is that the most recent lam's mpirun can take the
> same syntax as mpich's, though it has additional options as well.
> Could be mistaken on this, as am not too familiar with mpich.  

I think things are compatible as far as 

mpirun -np #machines programname  

is concerned ... and I guess that's the most important bit.

> > > Oh- and mpich doesn't have shared libs, so when you link -mpi
> > > and
> > > /etc/alternatives points to mpich, there are dangling symlinks for
> > > libmpi.so. :-(
> > Actually it is possible to build shared library for mpich, and
> > I tried it. It was not very exciting. 
> Not too exciting?  Sounds like real progress to me!  Is the latest
> mpich package equipped with these shared libs?=

The latest version does not have support for shared lib support built.
There is an option to build a shared lib, but I couldn't make it 
really work.

I'm not quite sure as to how to divide up the packages, but before
that I need to figure out the build system to get the building of
the shared libs right. The shared libs support is, erm, not very
good in the current version of upstream, especially in the build
process...

> Meanwhile, I've been discussing the binary compatibility issue with
> the lam authors, and it may not be quite as difficult as we had
> thought, (only if both implementations use shared libs, of course).
> Even if this were achieved, we'd have a Debian problem:  with the
> alternatives scheme, compiling against -lmpi will produce a binary
> with ldd reporting linkage against liblam or libmpich -- the compiler
> goes straight through the symbolic links.  Maybe this can be handled
> with a compiler/linker flag, but otherwise, we'd have to fall back on
> diversions (e.g. dpkg-divert) for libmpi.

Hmm... diversions are evil. Okay, let's see what could be done.
But first, I've gotta get shared libs version compiled.




regards,
	junichi

--
University: ti0113@mail4.doshisha.ac.jp    Netfort: dancer@netfort.gr.jp
dancer, a.k.a. Junichi Uekawa   http://www.netfort.gr.jp/~dancer
 Dept. of Knowledge Engineering and Computer Science, Doshisha University.
... Long Live Free Software, LIBERTAS OMNI VINCIT.