掌握该技术最根本的是需要搞清楚session跟踪文件存放的路径和生成跟踪文件的命名规则,不然,在已经存在成全上万trc文件的生产环
掌握该技术最根本的是需要搞清楚session跟踪文件存放的路径和生成跟踪文件的命名规则,不然,在已经存在成全上万trc文件的生产环境中,要想快速正确的找到跟踪其他SESSION产生的trc文件就如大海捞针。
跟踪其它session,一般是根据sid+serial#进行跟踪,但trc文件生成的名称跟SID和Serial#无关系,,只是根SPID有关系而已。
所以,搞清楚session跟踪文件存放的路径和生成跟踪文件的命名规则就非常重要了,下面来介绍一下。
1、 SESSION跟踪文件存放的路径
由数据库的user_dump_dest参数所决定,例如:
SQL> show parameter user_dump_dest
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
user_dump_dest string /dba/Oracle/diag/rdbms/litest/litest/trace
2、 SESSION跟踪文件的命名规则
“Instance_name” + “_ora_” + “spid.trc” 例如:
litest_ora_12262.trc
路径名+跟踪文件名示例即为:
/dba/oracle/diag/rdbms/litest/litest/trace/litest_ora_12262.trc
3、10046跟踪其它SID会话,寻找trc文件实例
(1)查询出目标会话的SID或SPID基本信息
A、先根据目标会话的SID查到其spid
SQL> select p.spid,s.sid,s.serial# from v$session s,v$process p where s.paddr=p.addr and s.sid=38;
SPID SID SERIAL#
------------------------ ---------- ----------
16334 38 1499
B、或者,根据目标会话的SPID查到其sid和serial#
SQL> select s.sid,s.serial#,p.spid from v$session s,v$process p where s.paddr=p.addr and p.spid=16334;
SID SERIAL# SPID
---------- ---------- ----------- -------------
38 1499 16334
从上面查询中,已经查出SID 38,Serail# 1499的SPID是16334
(2)10046跟踪目标会话(SID=38,SERIAL#=1499)
SQL> execute dbms_system.set_ev(38,1499,10046,12,'');
PL/SQL procedure successfully completed.
(3)在目标会话有产生活动信息后,根据目标会话的SPID 16334,到udump目示下寻找trc文件
[oracle@oraclelinux trace]$ pwd
/dba/oracle/diag/rdbms/litest/litest/trace
[oracle@oraclelinux trace]$ ls -l |grep 16334
-rw-r-----. 1 oracle oinstall 4703 Aug 15 13:42 litest_ora_16334.trc
-rw-r-----. 1 oracle oinstall 168 Aug 15 13:42 litest_ora_16334.trm
现在udump目录下已经找到10046跟踪SID为38的trc文件litest_ora_16334.trc,
文件的绝对路径+文件名为:/dba/oracle/diag/rdbms/litest/litest/trace/litest_ora_16334.trc
(4)最后别忘记停止对SID 38的跟踪哦
SQL> execute dbms_system.set_ev(38,1499,10046,0,'');
PL/SQL procedure successfully completed.

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