如何处理ORA-21780：Maximum number of object durations exceeded.

王亮

在11.2.0.4 RAC环境下，oracle两个节点中的alert日志，都反复在提示ORA-21780：Maximum number of object durations exceeded.的提示
如下：
Sun Jun 28 11:20:46 2020
Errors in file /u01/app/oracle/diag/rdbms/orcl/orcl1/trace/orcl1_smon_9425.trc:
ORA-21780: Maximum number of object durations exceeded.
Sun Jun 28 11:20:56 2020
Errors in file /u01/app/oracle/diag/rdbms/orcl/orcl1/trace/orcl1_smon_9425.trc:
ORA-21780: Maximum number of object durations exceeded.
Sun Jun 28 11:21:06 2020
Errors in file /u01/app/oracle/diag/rdbms/orcl/orcl1/trace/orcl1_smon_9425.trc:
ORA-21780: Maximum number of object durations exceeded.
Sun Jun 28 11:21:16 2020
Errors in file /u01/app/oracle/diag/rdbms/orcl/orcl1/trace/orcl1_smon_9425.trc:
ORA-21780: Maximum number of object durations exceeded.
Sun Jun 28 11:21:26 2020
Errors in file /u01/app/oracle/diag/rdbms/orcl/orcl1/trace/orcl1_smon_9425.trc:
ORA-21780: Maximum number of object durations exceeded.
Sun Jun 28 11:21:36 2020
Errors in file /u01/app/oracle/diag/rdbms/orcl/orcl1/trace/orcl1_smon_9425.trc:
ORA-21780: Maximum number of object durations exceeded.
Sun Jun 28 11:21:46 2020
Errors in file /u01/app/oracle/diag/rdbms/orcl/orcl1/trace/orcl1_smon_9425.trc:
ORA-21780: Maximum number of object durations exceeded.
Sun Jun 28 11:21:57 2020
Errors in file /u01/app/oracle/diag/rdbms/orcl/orcl1/trace/orcl1_smon_9425.trc:
ORA-21780: Maximum number of object durations exceeded.
Errors in file /u01/app/oracle/diag/rdbms/orcl/orcl1/trace/orcl1_smon_9425.trc:
ORA-21780: Maximum number of object durations exceeded.


查看对应的orcl1_smon_9425.trc文件，发现SMON信息一直在进行drop transient type,截取的内容如下：

*** 2020-06-28 11:21:16.840
SMON: following errors trapped and ignored:
ORA-21780: Maximum number of object durations exceeded.

*** 2020-06-28 11:21:26.880
         Drop transient type:   SYSTPqGZA3UOVevjgU2TwEKz/Hg==

*** 2020-06-28 11:21:26.880
SMON: following errors trapped and ignored:
ORA-21780: Maximum number of object durations exceeded.

*** 2020-06-28 11:21:36.924
         Drop transient type:   SYSTPqGZA3UOVevjgU2TwEKz/Hg==

*** 2020-06-28 11:21:36.924
SMON: following errors trapped and ignored:
ORA-21780: Maximum number of object durations exceeded.

*** 2020-06-28 11:21:46.965
         Drop transient type:   SYSTPqGZA3UOVevjgU2TwEKz/Hg==

*** 2020-06-28 11:21:46.965
SMON: following errors trapped and ignored:
ORA-21780: Maximum number of object durations exceeded.

*** 2020-06-28 11:21:57.004
         Drop transient type:   SYSTPqGZA3UOVevjgU2TwEKz/Hg==


通过MOS中的查找，这一情况命中Bug 7485772，且只在RAC环境中出现，通过这篇文章，简单地记录类似案例的两种处理方法：


方法一：
可以通过SQL语句：
select o.* from obj$ o, type$ t
where o.oid$ = t.tvoid and
bitand(t.properties,8388608) = 8388608 and (sysdate-o.ctime) > 0.0007; 查询出对应的事物信息，然后可以删除该job
语句如下：
DROP TYPE "SYSTPqGZA3UOVevjgU2TwEKz/Hg==" FORCE;


方法二：
可以通过设置事件22834来阻止SMON清除瞬态类型，如下所示。但是，这可能会导致瞬态类型增加。
操作步骤：

SQL> alter system set events '22834 trace name context forever, level 1';

System altered.

SQL> alter system set events '22834 trace name context off' ;

System altered.