library cache pin / lock

编译过程或者package时候，只要去编译，就会有library cache pin 等待，说明有session在访问这个对象，查v$access :

select b.sql_text text,a.sid sid ,a.serial# sria#,a.username username, c.type type,a.machine machine
from v$session a ,v$sqltext b ,v$access c
where c.object=upper('&1')
  and c.type in ('TABLE','PACKAGE','PROCEDURE')
  and a.sid=c.sid
  and b.address = a.sql_address
  and b.hash_value = a.sql_hash_value
order by a.sid,a.serial#,b.piece;

或者在v$session里查看该进程的final_blocking_session和final_blocking_instance定位锁住该进程的会话查看其在做什么，是否正常

select a.sid,a.final_blocking_session,a.final_blocking_instance,a.event from v$session a where a.sid = <your_sid>;

查看数据库中需要关注的等待事件：

select sw.seq#,sw.sid||','||s.serial# sids,s.username,sw.event,sw.P1,sw.p2,sw.p3,sw.wait_time "WAIT",
   sw.state,sw.seconds_in_wait sec,s.status,to_char(s.logon_time,'dd/hh24:mi:ss') logon_time
   from v$session s,v$session_wait sw
   where
   sw.sid =s.sid
   and s.username is not null
   and sw.event not like '%SQL*Net%'
   and sw.event not like 'PX Deq%'
   and sw.event not like 'rdbms ipc message'
   order by sw.event,s.username ;

如果系统中有大量library cache 等待，需要查出pin和lock的holder，然后杀掉.

a.查找pin holder 并kill:
 
select 'alter system kill session '''||a.sid||','||a.serial#||''';'
from v$session a,x$kglpn b
where a.saddr=b.kglpnuse  and b.KGLPNMOD<>0 and b.kglpnhdl in  (  select p1raw  from  v$session_wait  where event ='library cache pin');

b.查找lock holder 并kill
 
select 'alter system kill session '''||a.sid||','||a.serial#||''';'
 from v$session a, X$KGLLK b where  b.kgllkmod>0  and
 b.KGLLKHDL in  (  select p1raw  from  v$session_wait  where event ='library cache lock')
 and a.sid=b.KGLLKSNM   ;