有客户win 10.2.0.4的rac,查看alert日志发现如下错误

Mon May 04 17:25:18 2020
Errors in file d:\oracle\product\10.2.0\admin\orcl\bdump\orcl2_smon_2548.trc:
ORA-21779: 持续时间不活动
ORA-06512: 在 line 1

Mon May 04 17:25:28 2020
Errors in file d:\oracle\product\10.2.0\admin\orcl\bdump\orcl2_smon_2548.trc:
ORA-21779: 持续时间不活动
ORA-06512: 在 line 1

Mon May 04 17:25:38 2020
Errors in file d:\oracle\product\10.2.0\admin\orcl\bdump\orcl2_smon_2548.trc:
ORA-21779: 持续时间不活动
ORA-06512: 在 line 1

Mon May 04 17:25:39 2020
Errors in file d:\oracle\product\10.2.0\admin\orcl\bdump\orcl2_smon_2548.trc:
ORA-21779: 持续时间不活动
ORA-06512: 在 line 1

查看对应trace

Dump file d:\oracle\product\10.2.0\admin\orcl\bdump\orcl2_smon_2548.trc
Sat Aug 31 15:02:39 2019
ORACLE V10.2.0.4.0 - 64bit Production vsnsta=0
vsnsql=14 vsnxtr=3
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production
With the Partitioning, Real Application Clusters, OLAP, Data Mining
and Real Application Testing options
Windows Server 2003 Version V5.2 Service Pack 2
CPU                 : 32 - type 8664, 2 Physical Cores
Process Affinity    : 0x0000000000000000
Memory (Avail/Total): Ph:17543M/32742M, Ph+PgF:19550M/33833M

…………

*** 2020-05-04 18:40:35.687
SMON: following errors trapped and ignored:
ORA-21779: 持续时间不活动
ORA-06512: 在 line 1
*** 2020-05-04 18:40:45.734
	 Drop transient type:   SYSTPzpEA6olJSImGURLObkiE6w==
*** 2020-05-04 18:40:45.734
SMON: following errors trapped and ignored:
ORA-21779: 持续时间不活动
ORA-06512: 在 line 1
*** 2020-05-04 18:40:55.812
	 Drop transient type:   SYSTPzpEA6olJSImGURLObkiE6w==
*** 2020-05-04 18:40:55.812
SMON: following errors trapped and ignored:
ORA-21779: 持续时间不活动
ORA-06512: 在 line 1
*** 2020-05-04 18:41:05.875
	 Drop transient type:   SYSTPzpEA6olJSImGURLObkiE6w==
*** 2020-05-04 18:41:05.875
SMON: following errors trapped and ignored:
ORA-21779: 持续时间不活动
ORA-06512: 在 line 1

出现该问题是由于oracle的smon进程无法清理掉 transient types,从而出现该问题,根据官方的说法,这个错误是不会影响数据库正常使用,但是可以通过以下方法暂时规避这种错误:
1)通过设置alter system set events ’22834 trace name context forever, level 1′禁止smon清理transient types,从而来规避该错误,但是可能会引起transient types对象越来越多,当然你可以通过以下sql查询出来

select o.* from obj$ o, type$ t
where o.oid$ = t.tvoid and
bitand(t.properties,8388608) = 8388608 and (sysdate-o.ctime) > 0.0007;

然后删除掉相关记录DROP TYPE “SYSTPf/r2wN4keX7gQKjA3AFMSw==” FORCE;【这个删除不是必须的】
2) flush shared_pool也可以临时规避这个问题
3) 重启数据库,可以暂时规避

具体参考:
SMON: Following Errors Trapped And Ignored ORA-21779 (Doc ID 988663.1)
Receiving ORA-21780 Continuously in the Alert Log and SMON Trace Reports “Drop transient type”. (Doc ID 1081950.1)