Just an FYI for those of you working with slot_lists.
Lenny, Jeff and I have changed the mca param associated with how you specify the slot list you want the rank_file mapper to use. This was done to avoid the possibility of ORTE processes such as mpirun and orted accidentally binding themselves to cores. The prior param was identical to the one used to tell MPI procs their core bindings - so if someone ever modified the paffinity system to detect the param and automatically perform the binding, mpirun and orted could both bind themselves to the specified cores...which isn't what we would want.
The new param is "rmaps_base_slot_list". To make life easier, we also added a new orterun cmd line option --slot-list which acts as a shorthand for the new mca param.
Ralph