Oracle undo表空间爆满的解决

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mob604756eccc76 2013-04-03 20:09:00

1. 启动SQLPLUS，并用sys登陆到数据库。
#su - oracle  
$>sqlplus / as sysdba 

2. 查找数据库的UNDO表空间名,确定当前例程正在使用的UNDO表空间：
Show parameter undo_tablespace。

3. 确认UNDO表空间；
SQL> select name from v$tablespace;  
NAME  
------------------------------  
UNDOTBS1 

4. 检查数据库UNDO表空间占用空间情况以及数据文件存放位置；
select file_name, bytes / 1024 / 1024 / 1024
  from dba_data_files
 where tablespace_name like 'UNDOTBS%';

5. 查看回滚段的使用情况，哪个用户正在使用回滚段的资源，如果有用户最好更换时间（特别是生产环境）。
select s.username, u.name
  from v$transaction t, v$rollstat r, v$rollname u, v$session s
 where s.taddr = t.addr
   and t.xidusn = r.usn
   and r.usn = u.usn
 order by s.username;

查询结果为空的话就能删除。

6. 检查UNDO Segment状态；
select usn,
       xacts,
       rssize / 1024 / 1024 / 1024,
       hwmsize / 1024 / 1024 / 1024,
       shrinks
  from v$rollstat
 order by rssize;

USN  XACTS  RSSIZE/1024/1024/1024  HWMSIZE/1024/1024/1024  SHRINKS
8 0 0.00017547607421875 3.11521148681641  700
3 0 0.00023651123046875 3.22954559326172  632
0 0 0.00035858154296875 0.00035858154296875 0
1 0 0.00206756591796875 3.04867553710938  920
10  0 0.00206756591796875 0.648170471191406 819
7 0 0.00231170654296875 3.94835662841797  730
4 0 0.00304412841796875 2.00011444091797  651
11  0 0.00695037841796875 2.26921844482422  740
9 0 0.00792694091796875 2.07530975341797  773
6 0 0.00792694091796875 1.31906890869141  775
2 0 0.00890350341796875 3.13677215576172  699
5 0 1.96833801269531  3.99906921386719  267

这还原表空间中还存在12个回滚的对象。

7. 创建新的UNDO表空间，并设置自动扩展参数；
create undo tablespace undotbs2 datafile '/u02/pnrdb/undotbs2_01.dbf' size 100m reuse autoextend on next 100m maxsize unlimited;

8. 切换UNDO表空间为新的UNDO表空间 ， 动态更改spfile配置文件；

alter system set undo_tablespace=undotbs2 scope=both;  

9.验证当前数据库的 UNDO表空间
SQL> show parameter undo
NAME                                 TYPE        VALUE
------------------------------------ ----------- --------------
undo_management                      string      AUTO
undo_retention                       integer     900
undo_tablespace                      string      UNDOTBS2
9. 等待原UNDO表空间所有UNDO SEGMENT OFFLINE；
select usn,
       xacts,
       status,
       rssize / 1024 / 1024,
       hwmsize / 1024 / 1024,
       shrinks
  from v$rollstat
 order by rssize;

select usn,
       xacts,
       status,
       rssize / 1024 / 1024,
       hwmsize / 1024 / 1024,
       shrinks
  from v$rollstat
 order by rssize;
select t.segment_name, t.tablespace_name, t.segment_id, t.status
  from dba_rollback_segs t;

SEGMENT_NAME      TABLESPACE_NAME SEGMENT_ID   STATUS
_SYSSMU1$ UNDOTBS1  1 OFFLINE
_SYSSMU2$ UNDOTBS1  2 OFFLINE
_SYSSMU3$ UNDOTBS1  3 OFFLINE
_SYSSMU4$ UNDOTBS1  4 OFFLINE
_SYSSMU5$ UNDOTBS1  5 OFFLINE
_SYSSMU6$ UNDOTBS1  6 OFFLINE
_SYSSMU7$ UNDOTBS1  7 OFFLINE
_SYSSMU8$ UNDOTBS1  8 OFFLINE
_SYSSMU9$ UNDOTBS1  9 OFFLINE
_SYSSMU10$  UNDOTBS1  10  OFFLINE
_SYSSMU11$  UNDOTBS1  11  OFFLINE
_SYSSMU12$  UNDOTBS1  12  OFFLINE
_SYSSMU13$  UNDOTBS1  13  OFFLINE
_SYSSMU14$  UNDOTBS1  14  OFFLINE
_SYSSMU15$  UNDOTBS1  15  OFFLINE
_SYSSMU16$  UNDOTBS1  16  OFFLINE
_SYSSMU17$  UNDOTBS1  17  OFFLINE
_SYSSMU18$  UNDOTBS1  18  OFFLINE
_SYSSMU19$  UNDOTBS1  19  OFFLINE
_SYSSMU20$  UNDOTBS1  20  OFFLINE
_SYSSMU21$  UNDOTBS1  21  OFFLINE
_SYSSMU22$  UNDOTBS1  22  OFFLINE
_SYSSMU23$  UNDOTBS1  23  OFFLINE
_SYSSMU24$  UNDOTBS1  24  OFFLINE
_SYSSMU25$  UNDOTBS1  25  OFFLINE
_SYSSMU26$  UNDOTBS1  26  OFFLINE
_SYSSMU27$  UNDOTBS1  27  OFFLINE
_SYSSMU28$  UNDOTBS1  28  OFFLINE
_SYSSMU29$  UNDOTBS1  29  OFFLINE
_SYSSMU30$  UNDOTBS1  30  OFFLINE
_SYSSMU31$  UNDOTBS1  31  OFFLINE
_SYSSMU32$  UNDOTBS1  32  OFFLINE
_SYSSMU33$  UNDOTBS1  33  OFFLINE
_SYSSMU34$  UNDOTBS1  34  OFFLINE
_SYSSMU35$  UNDOTBS1  35  OFFLINE

上面对应的UNDOTBS1还原表空间所对应的回滚段均为OFFLINE
 
10.到$ORACLE_HOME/dbs/init$ORACLE_SID.ora如下内容是否发生变更：
#cat $ORACLE_HOME/dbs/initddptest.ora
……
*.undo_management=’AUTO’
*.undo_retention=10800
*.undo_tablespace=’UNDOTBS2’
……

如果没有发生变更请执行如下语句：
SQL> create pfile from spfile;
File created.

11. 删除原有的UNDO表空间；

drop tablespace undotbs1 including contents and datafiles;

12. os级别释放undo数据文件；

到root下执行
lsof |grep /u02/pnrdb/undotbs01.dbf

lsof |grep /u02/pnrdb/undotbs01.dbf |awk '{printf"kill -9 "$2"\n"}'