Bug 8627066, em dbconsole的bug

从3.237的监控机器上看到有waits的异常.

时间在昨晚10点左右.

 

为multi-block read.

猜测为表扫所导致的现象.

 

立马调出AWR报告看看.

Top 5 Timed Events                                         Avg%Total

~~~~~~~~~~~~~~~~~~                                       wait   Call

Event                                 Waits    Time (s)  (ms)   Time Wait Class

------------------------------ ----------------------- ------ ------ ----------

db file scattered read              414,758         712      2  26.5   User I/O

CPU time                                           681          25.3          

db file sequential read              76,454         414      5  15.4   User I/O

db file parallel write                8,284          11      1   0.4 System I/O

control file parallel write           1,759           9      5   0.3 System I/O

 

排在第一的是db file scattered read,
典型的全表扫描或索引快速全局扫描??

 

继续往下翻AWR报告吧.

 

 

SQL ordered by Gets

 

                                Gets              CPU     Elapsed              

  BufferGets   Executions    per Exec  %Total Time (s)  Time (s)    SQL Id   

-------------- ------------ ------------ -------------- --------- -------------

       46,155           60        769.3   0.8     1.80      6.54 6gvch1xu9ca3g

DECLARE job BINARY_INTEGER := :job; next_date DATE:= :mydate; broken BOOLEAN :

= FALSE; BEGINEMD_MAINTENANCE.EXECUTE_EM_DBMS_JOB_PROCS(); :mydate := next_date

; IF broken THEN :b := 1; ELSE :b := 0; END IF;END;

 

从SQL Orderedby gets上定位,

问题出在这个emdbconsole的程序,

翻阅资料,确认是bug

Bug 8627066: JOBEMD_MAINTENANCE.EXECUTE_EM_DBMS_JOB_PROCS() IS INCREASING LOAD ON DATABASE

 

看来这个问题再次发生的话,就考虑把EM关了.

emctl stop dbconsole