1 、故障描述
某用户某次SYSAUX表空间占用过大，为避免空间被打爆影响业务运行，需要定位具体哪些对象占用，以尽快使得SYSAUX表空间使用率处于合理区间。
查看v$sysaux_occupants确认占用空间对象select occupant_name,space_usage_kbytes from v$sysaux_occupants order by space_usage_kbytes desc; 查询结果：SM/ADVISOR 32741952
通过dba_segments进一步确认select segment_name,owner,tablespace_name,bytes/1024/1024"SIZE(MB)",segment_type from dba_segments where tablespace_name='SYSAUX' order by bytes desc; 查看结果：
WRI$_ADV_OBJECTS SYS SYSAUX 14497 TABLE
WRI$_ADV_OBJECTS_IDX_01 SYS SYSAUX 6907 INDEX
WRI$_ADV_OBJECTS_IDX_02 SYS SYSAUX 5761 INDEX
WRI$_ADV_OBJECTS_PK SYS SYSAUX 4804 INDEX
2 、排查处理
因为在12.2中，引入了新的特性：optimizer statistics advisor。优化器统计信息顾问每天都会在维护窗口运行，auto_stats_advisor_task多次运行，因而会消耗大量sysaux表空间。解决方案：
1 、删除statistics advisor task(auto_stats_advisor_task)，删除该任务后就可以释放统计信息产生的数据declare v_tname varchar2(32767);begin v_tname :='AUTO_STATS_ADVISOR_TASK'; dbms_stats.drop_advisor_task(v_tname);end;/
在删除任务的过程中，可能会遇到下面的错误：ORA-20001:Statistics Advisor: Invalid TaskName For thecurrent user
如果遇到上面的错误，可以先重建AUTO_STATS_ADVISOR_TASK来解决问题：SQL>connect as sysdbaSQL>EXEC DBMS_STATS.INIT_PACKAGE();
删除任务后，重新组织表和索引alter table wri$_adv_objects move;alter index wri$_adv_objects_idx_01 rebuild;alter index wri$_adv_objects_idx_02 rebuild;alter index wri$_adv_objects_pk rebuild;
如果 WRI$_ADV_OBJECTS 记录过多，delete以上会占用较大undo,可以把想要的数据存储在临时表，truncate table WRI$_ADV_OBJECTS，再insert回来。create table wri$_adv_objects_new tablespace ticket_dataas select * from wri$_adv_objectswhere task_id !=(select distinct id from wri$_adv_taskswhere name='AUTO_STATS_ADVISOR_TASK');SQL> select count(*)from wri$_adv_objects_new; COUNT(*)---------- 2968insert /*+ APPEND */ into wri$_adv_objectsselect * from wri$_adv_objects_new;
truncate 后查看空间占用：select OCCUPANT_NAME,OCCUPANT_DESC,SPACE_USAGE_KBYTES/1024 USAGE_MBfrom V$SYSAUX_OCCUPANTSorder by SPACE_USAGE_KBYTES DESC;SM/ADVISOR Server Manageability - Advisor Framework 6.1875
2 、缩短任务执行历史的保存时间
确认当前设定的保持期间（30天或UNLIMITED）
修改设定的保持期间
可以通过下面的命令，将EXECUTION_DAYS_TO_EXPIRE修改为15天，即执行历史数据的保存时间为7天：connect as sysdbaBEGIN DBMS_SQLTUNE.SET_TUNING_TASK_PARAMETER ( task_name => 'AUTO_STATS_ADVISOR_TASK' , parameter => 'EXECUTION_DAYS_TO_EXPIRE' , value => 15);END;/
3 、也可以禁用该任务，而不是删除。declare filter1 clob;begin filter1 := dbms_stats.configure_advisor_rule_filter('AUTO_STATS_ADVISOR_TASK', 'EXECUTE', NULL, 'DISABLE');END;/
