Newsgroups: comp.parallel.mpi From: "Joel R. Pullen" Subject: Re: MPI On Linux (Single Processor) Organization: University of Southern Mississippi Date: Thu, 11 Dec 1997 02:10:56 -0600 Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <348FA010.DB54120C@ocean.st.usm.edu> Ahmed Abukmail wrote: > Hi Guys, I just recently acquired RedHat Linux 4.2, and I was told that I > can install mpich on it. So I went to the argonne page and downloaded and > installed it. I compiled files and they worked fine. However after I > compiled and tried to run with multiple processors (mpirun -np 4 a.out), it > said permission denied. > > Someone at school told me that I can simulate multiple processors with a > single processor. If this is true, I would appreciate an answer on how to > do it. > > Thanks vary much > Ahmed > ahmed@cise.ufl.edu, or ahmed@magicnet.net Well, As written in the manual, you can use a process group file to do this simulation of multiple processors on your machine. It's kind of flaky but it'll work... just create a file procgroup.dat YourMachine 0 /thedirectory/program_name username YourMachine 1 /thedirectory/program_name username ................ Be sure to have the remote shell service working with .rhosts files.... Test it by rsh localhost ls run the program using the procgroup file mpirun -p4pg procgroup.dat [joel@Pullen][~/csc413/examples/basic]$ mpirun -p4pg grp srtest Process 0 on localhost 0 sending 'hello there' 0 receiving Process 1 on localhost Process 2 on localhost 0 received 'hello there' 1 receiving 1 received 'hello there' 1 sent 'hello there' 2 receiving 2 received 'hello there' 2 sent 'hello there' P4 procgroup file is grp. The is one of the example programs from the distribution that worked with the procgroup file.... Be sure to set one entry to '0' since it'll act as the master.... -Joel Pullen email: jrpullen@ocean.st.usm.edu