Hi jeffy, Thanks for your reply.
I am not understanding how MPI_Reduce would be useful. Say I have 3 processes and each process has array [1,2,3,4] When each process calculates the prefix sum using cuda each process will have array as [1,3,6,10] so if I use MPI_Reduce to gather results it returns me sum as 30. but the original array is [1,2,3,4,1,2,3,4,1,2,3,4] and the prefix sum of this array should be [1,3,6,10,11,13,16,20,21,23,26,30] Is my understanding wrong somewhere? On Fri, May 18, 2012 at 7:05 AM, Jeff Squyres <jsquy...@cisco.com> wrote: > You probably want MPI_Reduce, instead. > > http://www.open-mpi.org/doc/v1.6/man3/MPI_Reduce.3.php > > > On May 15, 2012, at 11:27 PM, Rohan Deshpande wrote: > > > I am performing Prefix scan operation on cluster > > > > I have 3 MPI tasks and master task is responsible for distributing the > data > > > > Now, each task calculates sum of its own part of array using GPUs and > returns the results to master task. > > > > Master task also calculates its own part of array using GPU. > > > > When each task returns its result (which would be array) master task > needs to combine all the results to get the final result. > > > > Can I use MPI_SCAN to combine the results? > > > > > > > > > > > > _______________________________________________ > > users mailing list > > us...@open-mpi.org > > http://www.open-mpi.org/mailman/listinfo.cgi/users > > > -- > Jeff Squyres > jsquy...@cisco.com > For corporate legal information go to: > http://www.cisco.com/web/about/doing_business/legal/cri/ > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users > -- Best Regards, ROHAN DESHPANDE
