ORA-600[4194]/[4193]解决

朋友的库启动的时候出现ORA-600[4194]/[4193]错误

Tue Feb 14 09:34:11 2012
Errors in file d:\oracle\product\10.2.0\admin\interlib\bdump\interlib_smon_2784.trc:
ORA-01595: error freeing extent (2) of rollback segment (3))
ORA-00607: Internal error occurred while making a change to a data block
ORA-00600: internal error code, arguments: [4194], [6], [30], [], [], [], [], []

Tue Feb 14 09:35:34 2012
Errors in file d:\oracle\product\10.2.0\admin\interlib\udump\interlib_ora_2824.trc:
ORA-00603: ORACLE server session terminated by fatal error
ORA-00600: internal error code, arguments: [4193], [2005], [2008], [], [], [], [], []
ORA-00600: internal error code, arguments: [4193], [2005], [2008], [], [], [], [], []

Tue Feb 14 09:36:30 2012
DEBUG: Replaying xcb 0x1fa24174, pmd 0x1fba06d4 for failed op 8
Doing block recovery for file 2 block 177
No block recovery was needed
Tue Feb 14 09:37:30 2012
Errors in file d:\oracle\product\10.2.0\admin\interlib\bdump\interlib_pmon_2732.trc:
ORA-00600: internal error code, arguments: [4193], [2005], [2008], [], [], [], [], []

Tue Feb 14 09:37:31 2012
Errors in file d:\oracle\product\10.2.0\admin\interlib\bdump\interlib_pmon_2732.trc:
ORA-00600: internal error code, arguments: [4193], [2005], [2008], [], [], [], [], []

从这里可以看到出现了ORA-600[4194]/[4193],第一感觉就是undo出现问题。
4193:表示undo和redo不一致(Arg [a] Undo record seq number,Arg [b] Redo record seq number );
4194:表示也是undo和redo不一致(Arg [a] Maximum Undo record number in Undo block,Arg [b] Undo record number from Redo block)
至于为什么有时候会只出现其中一个,我不太清楚,求答案

直接设置了下面参数,数据库就意外的open成功,这位朋友比较幸运

undo_tablespace=SYSTEM
undo_management=MANUAL

既然库已经open,然后新建undo空间,删除出问题的undo,做如下修改,数据库恢复完成

undo_tablespace=新undo
undo_management=AUTO

如果出现极端的情况可能需要做如下处理:
1.使用_offline_rollback_segments和_corrupted_rollback_segments屏蔽掉有问题的undo segment
2.继续可能出现ora-600[2662],需要推进scn

Query Duration=0与ORA-01555

1.ALERT日志错误
奇怪之处:Query Duration=0 sec,竟然出现了ORA-01555

Tue Feb  7 02:41:34 2012
ORA-01555 caused by SQL statement below (Query Duration=0 sec, SCN: 0x0b2e.efcd78a9):
Tue Feb  7 02:41:34 2012
SELECT "ID_NO","CUST_ID" FROM "DBACCADM"."DCUSTMSG" "C" WHERE "ID_NO"=:1

2.ORA-01555解释
超过了undo_retention时间,undo被覆盖导致ORA-01555

[zwq_acc1:/home/oraeye/check]oerr ora 1555
01555, 00000, "snapshot too old: rollback segment number %s with name \"%s\" too small"
// *Cause: rollback records needed by a reader for consistent read are
//         overwritten by other writers
// *Action: If in Automatic Undo Management mode, increase undo_retention
//          setting. Otherwise, use larger rollback segments

3.数据库版本

SQL> select * from v$version;

BANNER
----------------------------------------------------------------
Oracle9i Enterprise Edition Release 9.2.0.8.0 - 64bit Production
PL/SQL Release 9.2.0.8.0 - Production
CORE    9.2.0.8.0       Production
TNS for IBM/AIX RISC System/6000: Version 9.2.0.8.0 - Production
NLSRTL Version 9.2.0.8.0 - Production

4.undo基本信息
从这里可以发现,两个节点的undo表空间还有很多剩余,缺发生了undo被覆盖从而出现了ORA-01555

SQL> col name for a20
SQL> col value for a15
SQL> SELECT INST_ID, NAME, VALUE
  2    FROM GV$PARAMETER
  3   WHERE UPPER (Name) LIKE '%UNDO%';

   INST_ID NAME                 VALUE
---------- -------------------- ---------------
         1 undo_management      AUTO
         1 undo_tablespace      UNDOTBS1
         1 undo_suppress_errors FALSE
         1 undo_retention       1800
         2 undo_management      AUTO
         2 undo_tablespace      UNDOTBS2
         2 undo_suppress_errors FALSE
         2 undo_retention       1800

8 rows selected.


TABLESPACE_NAME                CURRENT_TOTAL(MB)   USED(MB)   FREE(MB)      FREE% AUT MAX_TOTAL(MB)
------------------------------ ----------------- ---------- ---------- ---------- --- -------------
UNDOTBS1                                   40950    1587.94 39362.0625      96.12 NO          40950
UNDOTBS2                                   57330    1926.31 55403.6875      96.64 NO          57330

SQL> SELECT DISTINCT STATUS ,
  2                  COUNT(*) "EXTENT_NUM",
  3                  SUM(BYTES) / 1024 / 1024 / 1024 "UNDO(G)"
  4    FROM DBA_UNDO_EXTENTS
  5   GROUP BY STATUS;

STATUS    EXTENT_NUM    UNDO(G)
--------- ---------- ----------
ACTIVE           208 .273658752
EXPIRED         7651 2.42865753
UNEXPIRED        941 .752548218

查询MOS[ID 761128.1],发现可能是Oracle bug导致(BUG:6799685 – ORA-1555 ERROR WITH QUERY DURATION=0 AND UNDO_RETENTION=1800和BUG:5475085 – V$UNDOSTAT.EXPBLKREUCNT IS NEVER INCREMENTED)

5.解决方法
Increase the size of the UNDO tablespace and increase the UNDO_RETENTION parameter value to try to prevent required undo expiring too quickly.
基于本库,因为undo空间还有很大剩余,直接设置UNDO_RETENTION=3600即可(可以从一定程度上缓解整个问题,但是要从根本上解决整个问题,需要升级到10.2.0.4及其以上版本)