如何释放v$session 中status=''KILLED''的进程

有些进程被杀掉之后一直没有被回收

session需要释放它所使用的资源，包括锁，回滚段 等资源；如果session已经运行了很长时间，kill session 可能是一个非常消耗时间的过程

察看session目前使用的回滚段块的数目信息
SELECT USED_UBLK FROM V$TRANSACTIOn a ,v$session b where a.addr=b.taddr;

你可以看看要回滚的数量
1.判断是否在回滚
select * from V$TRANSACTIOn where bitand(flag,power(2,7))>0
flag字段值可以标识事务类型
select to_char( 7811, ''0000000X'' ), to_char( 7683, ''0000000X'') from dual;

TO_CHAR(7 TO_CHAR(7
--------- ---------
00001E83 00001E03
^ ^
0 indicates "normal user transaction"
8 indicates "rollback,most likely - means no more changes and you cannot commit"

2.回滚量：UBABLK字段
3.查看回滚时间
col td format a40
col es format 999,999
col totalwork format 999,999
col units format a10
SELECT decode(target_desc,NULL,decode(target,NULL,opname, concat(opname, concat ('' - '',target))),decode(target,NULL,concat(opname, concat ('' : '',target_desc)),concat(opname, concat ('' : '',concat(target_desc,concat ('' - '',target)))))) td,sofar,totalwork,units, start_time,TO_CHAR(elapsed_seconds,''99999990.00''), decode(sofar, 0, 0, round(elapsed_seconds*(totalwork-sofar)/sofar)) 剩下的时间

FROM v$session_longops

WHERE sid = &v_sid

AND serial# =&v_serial#

and sofar< totalWork
D SOFAR TOTALWORK UNITS START_TIME TO_CHAR(ELAPSED_SECONDS,''99999 剩下的时间
------------------------------------ ----- --------- -------- ----------- ------------------------------ ----------
Table Scan - SINO.ACC_POENTRYD 16099 16099 Blocks 2005-4-15 1 8.00 0查看剩下的时间
4.你使用了alter session kill一个死进程，可能当时只是把session标识了killed，而v$process还存在，你可以用下面方法解决
UNIX平台
SQL> SELECT spid
FROM v$process
WHERE NOT EXISTS ( SELECT 1
FROM v$session
WHERE paddr = addr);

% kill
WINDOWS：
select p.spid "OS Thread", b.name "Name-User", s.osuser,
s.program
from v$process p, v$session s, v$bgprocess b
where p.addr = s.paddr
and p.addr = b.paddr
UNION ALL
select p.spid "OS Thread", s.username "Name-User",
s.osuser, s.program
from v$process p, v$session s
where p.addr = s.paddr
and s.username is not null; 使用orakill如
SQL> SELECT spid, osuser, s.program,sid
FROM v$process p, v$session s
WHERE p.addr=s.paddr;
SPID OSUSER PROGRAM SID
------------------------ -------------------- --------------- ----------
6484 lifeng.fang sqlplus.exe 11
SQL> host orakill charset 6484;

Kill of thread id 6484 in instance charset successfully signalled.
5.你可以在sqlnet.ora加dcd