throttle dont dispose users along the time which cause issues with memory along the time

Hello,

I am using gatling to put some static load on ur backend. Here is my snippet:

setUp(
scn.inject(
constantUsersPerSec(rps + 2) during duration,
).throttle(
warmUp ::: List(
jumpToRps(rps),
holdFor(duration))
).protocols(httpProtocol)
).maxDuration(duration)

The issue is related to throttle. It is working well in functional way i have constant rps but problem is with long tests, after arround 2 hours, despite the load. After this time i am start to recieve exceptions like java.lang.OutOfMemoryError. I think it is related with numbers of users, it is grows along the time which in my opinion cause issues with memory. Any idea how to dispose users? What I am doing wrong? i am attached image which shows signifacnt grow of active usrers.

Regards
Marcin