LH_LOAD_MULT
#define UP_LOAD (2*LH_LOAD_MULT) /* load times 256 (default 2) */
#define DOWN_LOAD (LH_LOAD_MULT) /* load times 256 (default 1) */
if (lh->up_load <= (lh->num_items * LH_LOAD_MULT / lh->num_nodes))
(lh->down_load >= (lh->num_items * LH_LOAD_MULT / lh->num_nodes)))