After I run ALTER SYSTEM KILL SESSION 'SID, SERIAL#' to kill one session, the session's status is changed to 'KILLED'. I have three questions:
1.When will the record of this session be removed from V$SESSION? I kill one session several hours ago, but now I can alse find it in V$SESSION.
2.Should it be kept until the database shutdown?
3.Are all the resources reserved for this session released?

BTW, as my Oracle is configed as MTS, those killed session hold my shared servers, just like the following:

USERNAME STATUS Query Location Disp Disp Status Serv Serv Status
------------------------------ -------- ---------------- ---- ---------------- ---- ----------------
SYS KILLED SERVER D025 WAIT S001 WAIT(RECEIVE)
SYS KILLED SERVER D014 WAIT S002 WAIT(RECEIVE)
SYS KILLED SERVER D024 WAIT S000 WAIT(RECEIVE)
SYS KILLED SERVER D028 WAIT S003 WAIT(RECEIVE)

select name,status from v$shared_server
NAME STATUS
---- --------------------
S000 WAIT(RECEIVE)
S001 WAIT(RECEIVE)
S002 WAIT(RECEIVE)
S003 WAIT(RECEIVE)
S004 WAIT(COMMON)
S005 WAIT(COMMON)
S006 WAIT(COMMON)


And all the first four shared server S000, S001, S002, S003 can not accept new requests, as if their are hung!