ORA-00054 故障处理一例
ORA-00054 故障处理一例
最近index job出现失败,于是尝试手动执行试试。收到了ORA-00054的错误消息。
一、错误消息
SQL> ALTER INDEX ESMDBA.ESM_PRCS_ERR_IDX1 rebuild;
ALTER INDEX ESMDBA.ESM_PRCS_ERR_IDX1 rebuild
*
ERROR at line 1:
ORA-00054: resource busy and acquire with NOWAIT specified
二、查看当前数据库中当前锁定对象
SQL> col OBJECT_NAME for a30
SQL> col username format a20
SQL> set linesize 200
SELECT object_name, s.username, s.sid, s.serial#, p.spid, to_char(s.logon_time,'yyyy-mm-dd hh24:mi:ss') logon_time
FROM v$locked_object l, dba_objects o, v$session s, v$process p
WHERE l.object_id = o.object_id
AND l.session_id = sSQL> 2 3 .sid
AND s.paddr = p.addr; 4 5
OBJECT_NAME USERNAME SID SERIAL# SPID LOGON_TIME
------------------------------ -------------------- ---------- ---------- ------------ -------------------
PLAN_TABLE A505995 622 15849 26577 2011-06-08 03:04:30
ESM_PRCS_ERR SMEVFP 396 60589 8388 2011-06-11 18:24:51
VNDR_FEED_SCHED SMEVFP 467 15860 3119 2011-06-11 22:30:48
BB_RF_VNDR_FEED_RCRD SMEVFP 467 15860 3119 2011-06-11 22:30:48
BB_RF_VNDR_REPSTRY SMEVFP 773 1079 8440 2011-06-11 18:24:55
BB_RF_VNDR_FEED_RCRD_DATA SMEVFP 467 15860 3119 2011-06-11 22:30:48
BB_RF_VNDR_FEED_RCRD_DATA SMEVFP 467 15860 3119 2011-06-11 22:30:48
7 rows selected.
三、查看表对象上信息
SQL> select OWNER,INDEX_NAME,TABLE_NAME,INDEX_TYPE from dba_indexes where INDEX_NAME like '%ESM_PRCS_ERR_IDX1%';
OWNER INDEX_NAME TABLE_NAME INDEX_TYPE
------------------------------ ------------------------------ ------------------------------ ---------------------
ESMDBA ESM_PRCS_ERR_IDX1 ESM_PRCS_ERR NORMAL
SQL> SELECT sql_text
2 FROM v$session, v$sqltext_with_newlines
3 WHERE decode(v$session.sql_hash_value, 0, prev_hash_value, sql_hash_value) =
v$sqltext_with_newlines.hash_value
AND v$session.sid = &sid
ORDER BY piece;
4 5 6 Enter value for sid: 396
old 5: AND v$session.sid = &sid
new 5: AND v$session.sid = 396
SQL_TEXT
----------------------------------------------------------------
SELECT ERR_OID, MQ_MSGE FROM ESM_PRCS_ERR WHERE ERR_OID = :1 FOR
UPDATE NOWAIT
四、进一步尝试
事实上此时做任何表结构的操作与分析都将会收到ORA-00054错误
SQL> analyze table ESMDBA.ESM_PRCS_ERR validate structure;
analyze table ESMDBA.ESM_PRCS_ERR validate structure
*
ERROR at line 1:
ORA-00054: resource busy and acquire with NOWAIT specified
SQL> analyze index ESMDBA.ESM_PRCS_ERR_IDX1 validate structure;
analyze index ESMDBA.ESM_PRCS_ERR_IDX1 validate structure
*
ERROR at line 1:
ORA-00054: resource busy and acquire with NOWAIT specified
五、杀掉锁定的会话
SQL> alter system kill session '396,60589';
System altered.
SQL> alter session set current_schema=ESMDBA;
Session altered.
SQL> show parameter db_name
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
db_name string O01GRS3
SQL> ALTER INDEX ESMDBA.ESM_PRCS_ERR_IDX1 rebuild;
Index altered.
六、原因
1.select for update
select for update是用于数据并发控制的语句。执行该语句后,会在表上加持RX锁(Row Exclusive,10gR1之前是Row Share锁),
在被选中记录上加行锁。但是,正是因为其加锁的操作,for update子句会导致select查询的性能下降。
2.关于select for update与select for update nowait
当使用 select for update 的时候,其他会话上与之相关的DML,DDL都会被挂起,直到会话select for update的锁定被解除。
当使用 select for update nowait 的时,其他会话上与之相关的DML,DDL都会被挂起不再是挂起,是直接返回一个资源忙的错误。
3.结论
无论是使用select ... for update 还是使用 select ... for update nowait。都会对相关的行集进行锁定,其他会话进行相关
行集的写操作都会被挂起,直到该锁定被解除。所以,在使用了select ... for update或者 select ... for update nowait 后,要
尽快解除锁定,避免其他会话挂起太久,从而导致系统性能下降。
评论暂时关闭