首页 > 代码库 > Oracle单实例情况下的library cache pin的问题模拟与问题分析
Oracle单实例情况下的library cache pin的问题模拟与问题分析
Oracle单实例情况下的library cache pin的问题模拟与问题分析
參考自:
WAITEVENT: "library cache pin" Reference Note (文档 ID 34579.1)
How to Find the Blocker of the ‘library cache pin‘ in a RAC environment? (文档 ID 780514.1)
本机环境:Oracle 10.2.0.5 x86-64bit for RHEL5.8 x86-64bit
第一个session:
[oracle@localhost ~]$ sqlplus / as sysdba SQL*Plus: Release 10.2.0.5.0 - Production on Fri Jun 12 17:27:28 2015 Copyright (c) 1982, 2010, Oracle. All Rights Reserved. Connected to an idle instance. SQL> startup ORACLE instance started. Total System Global Area 281018368 bytes Fixed Size 2095672 bytes Variable Size 96470472 bytes Database Buffers 176160768 bytes Redo Buffers 6291456 bytes Database mounted. Database opened. SQL> create user lc0019999 identified by aaaaaa; User created. SQL> grant dba to lc0019999; Grant succeeded. SQL> create user lc0029999 identified by aaaaaa; User created. SQL> grant dba to lc0029999; Grant succeeded. SQL> create user lc0039999 identified by aaaaaa; User created. SQL> grant dba to lc0039999; Grant succeeded. SQL> conn lc0019999/aaaaaa Connected. SQL> show user USER is "LC0019999" SQL> select * from v$mystat where rownum<2; SID STATISTIC# VALUE ---------- ---------- ---------- 159 0 1 SQL> Create or replace procedure dummy is 2 begin 3 null; 4 end; 5 / Procedure created. SQL> Begin 2 Dummy; 3 Dbms_lock.sleep(1000); 4 End; 5 / ------------>一直sleep着
以lc0029999登陆新开的一个session
[oracle@localhost ~]$ sqlplus lc0029999/aaaaaa SQL*Plus: Release 10.2.0.5.0 - Production on Fri Jun 12 17:34:04 2015 Copyright (c) 1982, 2010, Oracle. All Rights Reserved. Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options SQL> select * from v$mystat where rownum<2; SID STATISTIC# VALUE ---------- ---------- ---------- 158 0 1 SQL> SQL> alter procedure lc0019999.dummy compile; ------------>一直hang着
以sys用户新开一个session
[oracle@localhost ~]$ sqlplus / as sysdba SQL*Plus: Release 10.2.0.5.0 - Production on Fri Jun 12 17:31:33 2015 Copyright (c) 1982, 2010, Oracle. All Rights Reserved. Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options SQL> set line 200 SQL> select sid, serial#,event from v$session where event like ‘%library cache pin%‘; SID SERIAL# EVENT ---------- ---------- ---------------------------------------------------------------- 158 28 library cache pin SQL> select sid, serial#,p1raw,event from v$session where event like ‘%library cache pin%‘; SID SERIAL# P1RAW EVENT ---------- ---------- ---------------- -------------------------------------------------- 158 28 000000006BFF19B0 library cache pin SQL> col owner for a30 SQL> col object for a30 SQL> SELECT kglnaown "Owner", kglnaobj "Object" 2 FROM x$kglob 3 WHERE kglhdadr=‘000000006BFF19B0‘---->上面查出的P1RAW值。4 ; ---->该语句是查询出这个等待事件发生在哪个object上。 Owner Object ------------------------------ ------------------------------ LC0019999 DUMMY SQL> SQL> SELECT s.sid, kglpnmod "Mode", kglpnreq "Req" 2 FROM x$kglpn p, v$session s 3 WHERE p.kglpnuse=s.saddr 4 AND kglpnhdl=‘000000006BFF19B0‘;---->该语句是查询出这个等待事件的等待者sid(REQ>0)和持有者sid(Mode>0) SID Mode Req ---------- ---------- ---------- 158 0 3 159 2 0 SQL> ---补充:例如以下文字来源于: <blockquote><strong><code>Mode</code></strong><span> </span>is the mode in which the pin is wanted. This is a number thus:<ul><li>2 - Share mode</li><li>3 - Exclusive mode</li></ul></blockquote>
例如以下摘自:WAITEVENT: "library cache pin" Reference Note (文档 ID 34579.1) An X request (3) will be blocked by any pins held S mode (2) on the object. An S request (2) will be blocked by any X mode (3) pin held, or may queue behind some other X request.
Oracle单实例情况下的library cache pin的问题模拟与问题分析