Thanks this is good feedback. I was worried with the dynamic nature of Yarn containers that it would be hard to coordinate wire up, and you have confirmed that.
Thanks Brock Palen www.umich.edu/~brockp CAEN Advanced Computing XSEDE Campus Champion bro...@umich.edu (734)936-1985 > On Oct 27, 2014, at 11:25 AM, Ralph Castain <r...@open-mpi.org> wrote: > > >> On Oct 26, 2014, at 9:56 PM, Brock Palen <bro...@umich.edu> wrote: >> >> We are starting to look at supporting MPI on our Hadoop/Spark YARN based >> cluster. > > You poor soul… > >> I found a bunch of referneces to Hamster, but what I don't find is if it >> was ever merged into regular OpenMPI, and if so is it just another RM >> integration? Or does it need more setup? > > When I left Pivotal, it was based on a copy of the OMPI trunk that sat > somewhere in the 1.7 series, I believe. Last contact I had indicated they > were trying to update, but I’m not sure they were successful. > >> >> I found this: >> http://pivotalhd.docs.pivotal.io/doc/2100/Hamster.html > > Didn’t know they had actually (finally) released it, so good to know. Just so > you are aware, there are major problems running MPI under Yarn as it just > isn’t designed for MPI support. What we did back then was add a JNI layer so > that ORTE could run underneath it, and then added a PMI-like service to > provide the wireup support (since Yarn couldn’t be used to exchange the info > itself). You also have the issue that Yarn doesn’t understand the need for > all the procs to be launched together, and so you have to modify Yarn so it > will ensure that the MPI procs are all running or else you’ll hang in > MPI_Init. > >> >> Which appears to imply extra setup required. Is this documented anywhere >> for OpenMPI? > > I’m afraid you’ll just have to stick with the Pivotal-provided version as the > integration is rather complicated. Don’t expect much in the way of > performance! This was purely intended as a way for “casual” MPI users to make > use of “free” time on their Hadoop cluster, not for any serious technical > programming. > >> >> Brock Palen >> www.umich.edu/~brockp >> CAEN Advanced Computing >> XSEDE Campus Champion >> bro...@umich.edu >> (734)936-1985 >> >> >> >> _______________________________________________ >> users mailing list >> us...@open-mpi.org >> Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/users >> Link to this post: >> http://www.open-mpi.org/community/lists/users/2014/10/25593.php > > _______________________________________________ > users mailing list > us...@open-mpi.org > Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/users > Link to this post: > http://www.open-mpi.org/community/lists/users/2014/10/25613.php