+int unit_search_main_pid(Unit *u, pid_t *ret);
+int unit_watch_all_pids(Unit *u);
+
+int unit_get_memory_current(Unit *u, uint64_t *ret);
+int unit_get_tasks_current(Unit *u, uint64_t *ret);
+int unit_get_cpu_usage(Unit *u, nsec_t *ret);
+int unit_reset_cpu_usage(Unit *u);