V$session query run slow in one database campare with others

Problem Description

---------------------------------------------------

Database EXP11--> Elapsed: 00:00:55.05

Database Alba11--> Elapsed: 00:00:03.13

Version 11.2.0.4

SELECT sid ,

username ,

serial# ,

process ,

NVL(sql_id,0) ,

sql_address ,

blocking_session,

wait_class ,

event ,

p1 ,

p2 ,

p3 ,

seconds_in_wait

FROM v$session

WHERE blocking_session_status = 'VALID'

UNION

SELECT sid ,

username ,

serial# ,

process ,

NVL(sql_id,0) ,

sql_address ,

blocking_session,

wait_class ,

event ,

p1 ,

p2 ,

p3 ,

seconds_in_wait

FROM v$session

WHERE

(

sid ,

(

SELECT sys_context('USERENV', 'INSTANCE') FROM DUAL

)

)

IN

(

SELECT blocking_session ,

BLOCKING_INSTANCE

FROM v$session

WHERE blocking_session_status = 'VALID'

)

;