tst> select kglhdadr from x$kglob where kglnaobj='DBMS_SESSION';

KGLHDADR
----------------
00000003E3C369F0
00000003E2FEE8F0

tst> alter system flush shared_pool;

System altered.

tst> select kglhdadr from x$kglob where kglnaobj='DBMS_SESSION';

no rows selected

tst> select dbms_session.unique_session_id from dual;

UNIQUE_SESSION_ID
-----------------------------------------------------------------------------
002507C90001

tst> select kglhdadr from x$kglob where kglnaobj='DBMS_SESSION';

KGLHDADR
----------------
00000003EE90F7E0
00000003EE87AB58