Default Process Spawning

By default, mprun spawns multiple processes on SMPs. For example, if you have a two-node partition in which one node has two CPUs and the other has four CPUs, then the command

% mprun -np 6 a.out

runs six copies of a.out, two on the two-CPU node and four on the four-CPU node.

The -j and -R options override this behavior.

Alternatively, you can use the -Ns option to disable spawning of processes on individual CPUs of a node. Instead, -Ns will cause only one process to be started on each node.

Use the -Ys option to force spawning on nodes when used with -R. -Ys does not override -j.