pipe get wait event and performance issue

Hello,

This is regarding performance issue in 11g.The job used to complete in 3 hrs before but now it's taking more than 9 hrs.Please refer to the below output:

SQL> select sql_id,sid,last_call_et,status,event from v$session where username='XXMCK' and status='ACTIVE';

SQL_ID               SID LAST_CALL_ET STATUS   EVENT

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

771kjz38fm9td         11        23396 ACTIVE   pipe get

6rzkxckhdprkt        661        19478 ACTIVE   SQL*Net message from dblink

SQL> select se.event,sum(se.total_waits),sum(se.total_timeouts),sum(se.time_waited/100) time_waited from v$session_event se,v$session sess where sess.username='XXMCK' and sess.sid=se.sid group by se.event order by 2 desc;