(event_name LIKE 'wait/io/socket%',
                                CONCAT(IF (object_name LIKE ':0%', @@socket, object_name)),
                                object_name),
                            ''),
                          IF(index_name IS NOT NULL, CONCAT(' Index: ', index_name), ''),'\n'
                         ) AS event_name,
                  timer_wait, timer_start, nesting_event_id, source AS wait_info
             FROM performance_schema.events_waits_history_long WHERE thread_id = thd_id)) events
    ORDER BY event_id;
    RETURN CONCAT('{',
                  CONCAT_WS(',',
                            '"rankdir": "LR"',
                            '"nodesep": "0.10"',
                            CONCAT('"stack_created": "', NOW(), '"'),
                            CONCAT('"mysql_version": "', VERSION(), '"'),
                            CONCAT('"mysql_user": "', CURRENT_USER(), '"'),
                            CONCAT('"events": [', IFNULL(json_objects,''), ']')
                           ),
                  '}');
END