The Web Services pool concept, as configured in the Genero Application Server works quite well to make sure that there is the right number of fglrun processes running to service Web Service requests as they arrive. It balances the needs of servicing requests quickly without starting too many fglrun processes and consuming user licenses unnecessarily.
One of the simple things to remember is that there will be at least MIN_AVAILABLE number of processes running ready to service requests as they come in. What confuses some system administrators is that they will look on the server and there are no fglrun web_service_program processes running. This maybe due to the KEEP_ALIVE parameter.
Read more at
https://4js.com/ask-reuben/ig-228/