if (model != surf_host_model && model != surf_vm_model && model != surf_network_model &&
model != surf_storage_model) {
double next_event_model = model->next_occuring_event(NOW);
if (model != surf_host_model && model != surf_vm_model && model != surf_network_model &&
model != surf_storage_model) {
double next_event_model = model->next_occuring_event(NOW);