ev_timer_stop (event_base, &IO->rw_timeout);
ev_timer_stop(event_base, &IO->conn_fail);
ev_idle_stop(event_base, &IO->unwind_stack);
ev_timer_stop (event_base, &IO->rw_timeout);
ev_timer_stop(event_base, &IO->conn_fail);
ev_idle_stop(event_base, &IO->unwind_stack);