enq: TX - row lock contention 等待事件

Oracle 数据库发生等待事件:enq: TX - row lock contention ,排查思路 遇到 enq:TXrowlockcontention 等待事件,如何排查? 阅读详情

OS环境:windows server 2008 64位

数据库版本:11.2.0

 

今天在使用rman备份的时候随意的查看了一下等待事件,除了了我们现在系统遇到的IO瓶颈外,还额外的发了enq: TX - row lock contention该等待事件

 

1:查询当前系统的等待事件

 

select event,sid,p1,p2,p3 from v$session_wait where event not like 'SQL*%' and event not like 'rdbms%';


EVENT                                   SID         P1              P2             P3
----------------------------------     ----      ----------       ----------    ----------
enq: TX - row lock contention     4    1415053318     196638        55836
RMAN backup & recovery I/O      5            1               256       2147483647
enq: TX - row lock contention    12    1415053318     524293        51153
RMAN backup & recovery I/O     25           1                256      2147483647
db file sequential read             27          16             2876703         1
pmon timer                             33         300                0               0
db file scattered read               39          33              790536         128
VKTM Logical Idle Wait            49           0                   0               0
Streams AQ: qmn slave idle wait         50          1          0          0
asynch descriptor resize           53     

(第82天)enq: TX - row lock contention 等待事件分析 最近看 awr 报告时,经常会看到一些的等待事件,分享一下排查的步骤。用于在事务执行时维护事务的完整性,防止其他会话同时修改相同的数据。如果发生争用,‘enq: TX - row lock contention’ 很可能成为数据库时间的重要组成部分并影响其他会话的性能。一旦发现数据库存在严重的 ‘enq: TX - row lock contention’ 等待,需要做的就是找出对应的对象和所涉及的 SQL 语句。通常等待与正在执行的应用程序代码有关,数据库本身大概率不存在问题。产生。 阅读详情

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