造成library cache lock的常見原因：

1、回收站oracle recyclebin

2、重建索引

3、收集資料庫統計資訊

4、11g密碼延遲特性

cursor: mutex S、kksfbc child completion、library cache lock造成資料庫cpu100%

觸發Oracle的bug：10636231

解決方案：

版本11.1.0.7
SQL> alter system set "_cursor_features_enabled"=18 scope=spfile;
System altered.
SQL> alter system set event='106001 trace name context forever,level 1024' scope=spfile;
System altered.
並重啟例項

版本11.2.0.1
 
SQL> alter system set "_cursor_features_enabled"=34 scope=spfile;
System altered.
SQL> alter system set event='106001 trace name context forever,level 1024' scope=spfile;
System altered.

版本11.2.0.2
SQL> alter system set "_cursor_features_enabled"=1026 scope=spfile;
System altered.
SQL> alter system 
 
set event='106001 trace name context forever,level 1024' scope=spfile;
System altered.

版本11.2.0.3+
alter system set "_cursor_obsolete_threshold"=1024 scope=spfile;