今天网友给我一份AWRRPT TOP5如下：
| cursor: mutex S | 71,373,261 | 295,337 | 4 | 73.78 | Concurrency |
| DB CPU | 30,974 | 7.74 | |||
| library cache lock | 560,800 | 18,037 | 32 | 4.51 | Concurrency |
| db file sequential read | 1,168,603 | 8,481 | 7 | 2.12 | User I/O |
| enq: TX - row lock contention | 11 | 8,106 | 736927 | 2.03 | Application |
而TOP Elapsed Time 的语句是
| Elapsed Time (s) | Executions | Elapsed Time per Exec (s) | %Total | %CPU | %IO | SQL Id | SQL Module | SQL Text |
|---|---|---|---|---|---|---|---|---|
| 326,330.72 | 81.52 | 2.86 | 4vs91dcv7u1p6 | insert into sys.aud$( sessioni... |
明显这里和审计有关，既然不是用户自己的application sql，第一感觉应该是BUG，然后再metalink找到如下文档，确认是BUG
Database Hangs With Excessive Cursor Mutex S Waits Due to Sys.Aud$ Cursors [ID 1423386.1] 转到底部
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修改时间:2012-2-27类型:PROBLEM状态:MODERATED优先级:3 注释 (0)
In this Document
Symptoms
Cause
Solution
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This document is being delivered to you via Oracle Support's Rapid Visibility (RaV) process and therefore has not been subject to an independent technical review.
Applies to:
Oracle Server - Enterprise Edition - Version: 11.2.0.1 and later [Release: 11.2 and later ]
Information in this document applies to any platform.
Symptoms
Database hangs with excessive cursor mutex S waits.
AWR reports
o Top wait event: cursor: mutex S and library cache lock
o high version count [1526] for sqlid :
4vs91dcv7u1p6 - insert into sys.aud$ ....
Trace file from event errorstack of session that was waiting shows:
o call stack
kksMutexWait kgxWait kgxShared kkshGetNextChild kkscsSearchChildLis kksfbc kkspsc0 kksParseCursor ....
o current sql:
insert into sys.aud$( sessionid,entryid,statement,ntimestamp#, userid,userhost,terminal,action#,returncode, obj$creator,obj$name,auth$privileges,auth$grantee, new$owner,new$name,ses$actions,ses$tid,logoff$pread, logoff$lwrite,logoff$dead,comment$text,spare1,spare2, priv$used,clientid,sessioncpu,proxy$sid,user$guid, instance#,process#,xid,scn,auditid, sqlbind,sqltext,obj$edition,dbid) values(:1,:2,:3,SYS_EXTRACT_UTC(SYSTIMESTAMP), :4,:5,:6,:7,:8, :9,:10,:11,:12, :13,:14,:15,:16,:17, :18,:19,:20,:21,:22, :23,:24,:25,:26,:27, :28,:29,:30,:31,:32, :33,:34,:35,:36)
Cause
Issue is similar to the report in:
Bug 11936699
Abstract: WAIT TIME OF LIBRARY CACHE LOCK INCREASES DUE TO MANY CHILD CURSORS OF SYS.AUD$
Solution
Apply patches: 10151017, 9944129, and 10636231 if available for version / platform
OR
Apply 11.2.0.3 patchset which includes all 3 fixes
相关内容 …
产品 …
•Oracle Database Products > Oracle Database > Oracle Database > Oracle Server - Enterprise Edition > RDBMS > Database Level Performance Issues (not SQL Tuning)
关键字 …
HIGH VERSION COUNT;MUTEX;SYS.AUD$
安装补丁即可