Hi, I haven't used the more mpi process also but still am still unable to reduce my exection time.Here is my code *http://seshendramln.blogspot.se/* and please help me in solving. In this code iam getting the same execution time in i increase or decrease the no.of nodes.
thanking you With regards seshendra On Fri, May 4, 2012 at 12:55 PM, Jeff Squyres <jsquy...@cisco.com> wrote: > You probably need to be more fine-grained in your timing. Find out > exactly what is increasing in time. This is a common symptom for codes > that do not scale well -- i.e., adding more MPI processes actually causes > it to slow down. > > > On May 3, 2012, at 7:48 AM, seshendra seshu wrote: > > > Hi, > > I have written an parallel program and when i run my program on 4,8,16 > nodes and calculated the execution time at master using MPI_Wtime in master > node. The problem the execution time is increasing rapidly like NON > parallel program-55 sec, and for parallel program 2-nodes--60sec , 4-nodes > 74sec, 8-node--120 sec and for 16 nodes---for 180 sec. can i know my > problem in parallel version actually the time needs to be decreased but it > is increasing i dont the reason. i have calculated my time as shown below > > > > > > main(argv,argc) > > { > > double start,end; > > start= MPI_Wtime; > > // done some work > > { > > // start send from master node and receiving it > > end =MPI_Wtime; > > cout<<"execution time"<<end-start; > > } > > //in slave nodes done some work > > MPI_Finalize; > > } > > > > Please help me in solving this problem. > > > > -- > > WITH REGARDS > > M.L.N.Seshendra > > _______________________________________________ > > 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 > -- WITH REGARDS M.L.N.Seshendra