macOS openMPI and Macosx

sioannou said:

I've spent a lot of hours searching the web for some information however openMPI lacks proper documentation. From what I read it seems that openMPI is already installed in macosx (snow leopard) but without the fortran compiler?

Click to expand...

It is definitely there. You can use either C or C++ with it (I think you still need to use the GCC compiler as I don't think LLVM supports it yet).

Alternatively you could compile your own GCC Fortran compiler and your own version of OpenMPI if you have to use Fortran. That is pretty straightforward.

Checkout MacPorts; it has OpenMPI built with gfortran. I haven't tested it because I compile my own with Intel Fortran, but it should work.

crackpip

crackpip said:

Checkout MacPorts; it has OpenMPI built with gfortran. I haven't tested it because I compile my own with Intel Fortran, but it should work.

crackpip

Click to expand...

Yes, it is all there in MacPorts. I used it a couple of years ago, but not lately, so I can't swear that there are no current problems, but definitely try installing the MacPorts versions.

I know this thread is dead, but I'm going to revive it to explain how to properly install OpenMPI w/FORTAN support for those who may search in the future.

-First and foremost install XCode (so that you have a relavant c++ compiler on the machine as it will be necessary in later steps)
--This can either be done from the MacOSx install disc or from the App Store/Dev portal

-Secondly install GFortran (binaries can be found here http://gcc.gnu.org/wiki/GFortranBinaries#MacOS )

-Lastly go to http://www.open-mpi.org and download the .tar.gz of the current version's source (if this thread is still relevant when you are reading this can be done from this link http://www.open-mpi.org/software/ompi/v1.4/ but make sure it is the most up to date version)
--you can use stuffit expander (free in app store) to untar or use the unix commands, up to you

---- now for the building OpenMPI portion...
-Go into terminal and type 'gfortran -v' and verify that your gfortran is the version you installed in the steps above
-- if not type 'which gfortran' and see which gfortran it is sourcing.. if it is still sourcing apples xcode gfortran without OpenMPI support then simple modify your .profile/.bashrc/.cshrc or whatever to source the new gfortran you installed

--now in teminal cd to your openmpi directory (wherever you extracted it)
--decide where you want to install openmpi... if you want to install over the factory mac install, type 'which mpif90' to see the location of your current mpi install... will more then likely be /usr/bin
--in terminal in the openmpi extracted directory type 'sudo ./configure --PREFIX=/whereyouwanttoinstall'
--then type 'sudo make all install'

so for example if you want to overwrite xcodes default ompi install, you would do
sudo ./configure --PREFIX=/usr/bin
sudo make all install

*note if you install to a location other then the default ompi directory you will need to update your .profile/.bashrc/.cshrc
Simply add the line:
export PATH=$PATH:/myompidirectory/
where myompidirectory is the PREFIX you used...

close terminal.. and open it back up (or type 'source .profile' or whatever terminal source you use) and now we check if it installed correctly

type 'which mpif90'
It should spit out the correct location of your openmpi install...
now type 'mpif90 '
if you receive the message 'gfortran: no input files' then you did it all correctly
if you receive a message that the current version does not support fortran blah blah then something went wrong in your installation process and you still have the xcode openmpi that does not support fortran

Hope this helps someone in the future... it was a pain in the butt doing the first time