if(network_update_mechanism == UM_LAZY){
net_action_heap = xbt_heap_new(8,NULL);
xbt_heap_set_update_callback(net_action_heap, net_action_update_index_heap);
if(network_update_mechanism == UM_LAZY){
net_action_heap = xbt_heap_new(8,NULL);
xbt_heap_set_update_callback(net_action_heap, net_action_update_index_heap);