use FMS AutoCloseIdleClients But invalid

Help, Help

I use the FMS3.0.1,I want to keep the user's client on the FMS that i can call client's function.

I'm sure that i never change the Server.xml,Vhost.xml,Application.xml.

The AutoCloseIdleClients default value is closed, user's client will not be closed.But in my application,the user client will be closed by a few times.I don't know why?

So i changed the Server.xml to enabled the AutoCloseIdleClients,and set the CheckInterval values 10000 and MaxIdleTime values 72000.

But the question is still exist!Why?

I want to ask the other question:

Whether the configuration files priority like this:

app's Application.xml > server's Application.xml > VHost.xml > Server.xml?

Thanks.

Why nobody can help me?