Ada: Execution of a parallel MPI code in interactive mode

The execution of a parallel MPI program in interactive mode on Ada is limited by the following:

  • Elapsed time (clock time) : 30mn
  • Memory for each MPI task < 3.5GB
  • Number of tasks (< 32)

The following is an example of an interactive execution of a parallel program on 4 processors (for an executable file named poisson_MPI):

$ export MP_PROCS=4
$ poe ./poisson_MPI

or directly:

$ poe ./poisson_MPI -procs 4

In the event that the processors are not available, you will obtain the following message:

ERROR: 0031-365  LoadLeveler unable to run job, reason:
LoadL_negotiator: 2544-870 Step was not considered
to be run in this scheduling cycle due to its relatively
low priority or because there are not enough free resources.

If the program requires more resources, it will have to be submitted in batch mode.