Open MPI logo

Open MPI User's Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Open MPI User's mailing list

Subject: Re: [OMPI users] MPI and C++ (Boost)
From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2009-07-07 08:26:27


I think you face a common trade-off:

- use a well-established, debugged, abstraction-rich library
- write all of that stuff yourself

FWIW, I think the first one is a no-brainer. There's a reason they
wrote Boost.MPI: it's complex, difficult stuff, and is perfect as
middleware for others to use.

If having users perform a 2nd step is undesirable (i.e., install Boost
before installing your software), how about embedding Boost in your
software? Your configure/build process can certainly be tailored to
include Boost[.MPI]. Hence, users will only perform 1 step, but it
actually performs "2" steps under the covers (configures+installs
Boost.MPI and then configures+installs your software, which uses Boost).

FWIW: Open MPI does exactly this. Open MPI embeds at least 5 software
packages: PLPA, VampirTrace, ROMIO, libltdl, and libevent. But 99.9%
of our users don't know/care because it's all hidden in our
configure / make process. If you watch carefully, you can see the
output go by from each of those configure sections when running OMPI's
configure. But no one does. ;-)

Sidenote: I would echo that the Forum is not considering including
Boost.MPI at all. Indeed, as mentioned in different threads, the
Forum has already voted once to deprecate the MPI C++ bindings, partly
*because* of Boost. Boost.MPI has shown that the C++ community is
better at making C++ APIs for MPI than the Forum is. Hence, our role
should be to make the base building blocks and let the language
experts make their own preferred tools.

On Jul 7, 2009, at 5:03 AM, Matthieu Brucher wrote:

> > IF boost is attached to MPI 3 (or whatever), AND it becomes part
> of the
> > mainstream MPI implementations, THEN you can have the discussion
> again.
>
> Hi,
>
> At the moment, I think that Boost.MPI only supports MPI1.1, and even
> then, some additional work may be done, at least regarding the complex
> datatypes.
>
> Matthieu
> --
> Information System Engineer, Ph.D.
> Website: http://matthieu-brucher.developpez.com/
> Blogs: http://matt.eifelle.com and http://blog.developpez.com/?blog=92
> LinkedIn: http://www.linkedin.com/in/matthieubrucher
> _______________________________________________
> users mailing list
> users_at_[hidden]
> http://www.open-mpi.org/mailman/listinfo.cgi/users
>

-- 
Jeff Squyres
Cisco Systems