Hi RMA operations exist since MPI 2.0. There are some new functions in MPI 3.0, but I don't think you will need them.
I'm currently working on a library that provides access to large grids. It uses RMA and it works quite well with MPI 2.0. Best regards, Sebastian > Hi > > Thank You all for your replies. > I'll certainly look into the MPI 3.0 RMA link (out of pure interest) > but i am afraid i can't go bleeding edge, because my application > will also have to run on an other machine. > > As to OpenMP: i already make use of OpenMP in some places (for > instance for the creation of the large data block), > but unfortunately my main application is not well suited for OpenMP > parallelization.. > > I guess i'll have to take more detailed look at my problem to see if i > can restructure it in a good way... > > Thank You > Jody > > On Mon, Apr 16, 2012 at 11:16 PM, Brian Austin <brianmaus...@gmail.com> wrote: > > Maybe you meant to search for OpenMP instead of Open-MPI. > > You can achieve something close to what you want by using OpenMP for > > on-node parallelism and MPI for inter-node communication. > > -Brian > > > > > > > > On Mon, Apr 16, 2012 at 11:02 AM, George Bosilca <bosi...@eecs.utk.edu> > > > > wrote: > >> No currently there is no way in MPI (and subsequently in Open MPI) to > >> achieve this. However, in the next version of the MPI standard there will > >> be a function allowing processes to shared a memory segment > >> (https://svn.mpi-forum.org/trac/mpi-forum-web/ticket/284). > >> > >> If you like living on the bleeding edge, you can try Brian's branch > >> implementing the MPI 3.0 RMA operations (including the shared memory > >> segment) from http://svn.open-mpi.org/svn/ompi/tmp-public/mpi3-onesided/. > >> > >> george. > >> > >> On Apr 16, 2012, at 09:52 , jody wrote: > >> > Hi > >> > > >> > In my application i have to generate a large block of data (several > >> > gigs) which subsequently has to be accessed by all processes (read > >> > only), > >> > Because of its size, it would take quite some time to serialize and > >> > send the data to the different processes. Furthermore, i risk > >> > running out of memory if this data is instantiated more than once on > >> > one machine. > >> > > >> > Does OpenMPI offer some way of sharing data between processes (on the > >> > same machine) without needing to send (and therefore copy) it? > >> > > >> > Or would i have to do this by means of creating shared memory, writing > >> > to it, and then make it accessible for reading by the processes? > >> > > >> > Thank You > >> > Jody > >> > _______________________________________________ > >> > users mailing list > >> > us...@open-mpi.org > >> > http://www.open-mpi.org/mailman/listinfo.cgi/users > >> > >> _______________________________________________ > >> users mailing list > >> us...@open-mpi.org > >> http://www.open-mpi.org/mailman/listinfo.cgi/users > > > > _______________________________________________ > > users mailing list > > us...@open-mpi.org > > http://www.open-mpi.org/mailman/listinfo.cgi/users > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users
