 on allocation of owned atom 
    arrays 
    <LI>
    2nd parameter = extra_ghost = padding factor on allocation of ghost 
    atom arrays 
    <LI>
    3rd parameter = extra_neigh = padding factor on allocation of neighbor 
    lists 
    <LI>
    4th parameter = extra_buf = padding factor on allocation of 
    communication buffers 
</UL>
<PRE>

factors that affect how much extra memory is allocated when a problem is setup
factor of 1.0 means no padding (use exactly what LAMMPS estimates is
  needed), fa