If you instantiate a remote persistent procedure in a session-free application, any network resource that provides the bound connection for the client is unavailable for other clients until that remote persistent procedure is deleted (or released for an Open Client or SOAP Web service ProcObject). If enough clients simultaneously create and use instances of this persistent procedure, the PAS for OpenEdge instance might have no more ABL sessions available in its session pool to serve additional clients.
Thus, if all clients that use the business application are always required to create an instance of this remote persistent procedure, the business application is scalable only for the number of clients that can simultaneously create that remote persistent procedure. Even if clients are not required to create this persistent procedure for all uses of the business application, any clients that do so reduce the availability of network resources to other clients and limit the scalability of the business application accordingly.
Thus, to allow a session-free business application to scale fully for the network resources available, do not allow any clients to instantiate remote persistent procedures. For Open Client and SOAP Web service applications, you can do this by not defining any ProcObjects in the Open Client interface.