Process tracing

Hello,

I am going to test the difference between mpirun and mpiexec on LSF.
The following manual says that mpirun is related to LSF.
(https://software.intel.com/en-us/mpi-developer-reference-linux-mpirun)

1. I would like to see what physical process mpirun and mpiexec use when working through LSF.
   Can the "-trace" command confirm which physical processes are being used?

2. Since there is a case where mpiexec is faster, I want to use mpiexec instead of mpirun.
    Is there a disadvantage of not being recognized by job scheduler?

Thanks