[Pkg-openmpi-maintainers] Bug#376833: Bug#376833: Open bug reports on OpenMPI for 'no atomic primitives' on s390, hppa and m68k

[Dirk Eddelbuettel]

On 1 March 2008 at 16:17, Riku Voipio wrote:
| On Thu, Feb 21, 2008 at 09:26:25AM -0600, Dirk Eddelbuettel wrote:
| > You can do what I did for Rmpi and use Open MPI where available and LAM where
| > not:
| 
| >       Build-Depends: debhelper (>> 4.1.0), cdbs, r-base-dev (>= 2.6.0), \
| > 	libopenmpi-dev (>= 1.2.4-5) [i386 amd64 alpha ia64 powerpc sparc], \
| > 	lam4-dev [!i386 !amd64 !alpha !ia64 !powerpc !sparc]
| 
| > Nothing wrong with that.
| 
| I think a portable solution would be better.

"Would" and "could" are great terms as there are millions of things we
"could" improve around Debian. :)

But we *do* currently build against MPI -- either Open MPI or LAM -- on all
arches, so in my book the matter is at worst somewhat aethestically
unpleasant, but not all that urgent.
 
| > | Why not use libatomic-ops which includes atomic primitives for all
| > | supported architectures and more?
| 
| > Are you sure that these atomic ops are the one mssing in Open MPI?  Could you
| > provide a proof of concept for one arch so that I could take that to upstream?
| 
| I don't really know anything about openmpi internals, but looking at
| atomic-powerpc32-linux.s all but opal_sys_timer_get_cycles have similar
| definitions in libatomic-ops-dev.

Our invitation is still open -- come join the open-mpi lists and discuss it
there.  We need people with actual knowledge of a given arch, and access to
such a box to do some testing. I'd help, but I know little beyond x86 and
even then little about architecture matters.   So join in the effort and make
change happen.

On the other hand, just standing on a soap box and wishing for a pony won't
solve the issue. That's why the bug report is open.  We brought it up once or
twice on list and some people volunteered ... only to disappear thereafter.

I really do appreciate the follow-up, but we need more concrete next steps.

Dirk

-- 
Three out of two people have difficulties with fractions.