Many sessions GLOGDBA

Good day!

My version OTM 6.4.3, Fusion Middlewhare - 12.2.1

I use this query:

select username, machine, count (*) from v$session group by username, machine order by 3 desc.

Result:

   USERNAME MACHINE COUNT(*)

1 GLOGDBA prod02 492

2 GLOGDBA prod01 152

When some time passes i got very much Inactive sessions, containing this query:

select dummy from dual

Count sessions one day was 2500 for prod01 and 2500 for prod2. I have limit for processes and sessions - 5000. This problem was solved only by restarting OTM!

Please help me!