Users can log into Euclid using the Secure Shell (SSH) protocol 2 with the following command:
% ssh -l username euclid.nersc.gov
When you successfully log in you will land in your $HOME directory.
Euclid is a one node system. All jobs that run on Euclid, e.g. compiles, edits, user jobs, etc,. run on the same node.
Sample Program Code: Parallel Hello World
Although Euclid was not intended for production runs of MPI codes, it is possible to run small MPI codes on it.
Open a new file called helloWorld.f90 with a text editor such as emacs or vi. Paste the contents of the below code into the file.
integer :: myPE, numProcs, ierr
call MPI_COMM_RANK(MPI_COMM_WORLD, myPE, ierr)
call MPI_COMM_SIZE(MPI_COMM_WORLD, numProcs, ierr)
print *, "Hello World from ", myPE
end program helloWorld
Compiling the Program
% mpif90 -o helloWorld helloWorld.f90
Running the Job
Euclid does not have a batch system. All jobs are truly interactive and all run on the single 48 core node, sharing it with all other interactive users and all other processes.
To launch the job with 8 MPI processes, use the mpirun job launcher on the command line:
% mpirun -np 8 ./helloWorld
The job will start running instantaneously and will display this output to the screen when it is completed:
Hello World from 2
Hello World from 3
Hello World from 1
Hello World from 0
Hello World from 6
Hello World from 5
Hello World from 7
Hello World from 4