Scalability demands that individual clients do not consume significant server resources indefinitely. A large number of infrequent users should not require that the system is hosted on super-server hardware. Server host sizing should be a function of transaction throughput, not of user count.

The Java I/O model, in particular the Java RMI implementation, dedicates at least one thread to each network connection. To make this scalable to a large number of users, Windchill implements two mechanisms to free network connections and threads. The first is to time out connections that remain idle for a specified period of time. The second is to limit the total number of client sockets the RMI runtime is allowed to consume. This limit is enforced by closing the least-recently-used connect. Thus, new client connections are not refused, and connection timeout is faster when under a heavy client load. Clients recover from the disconnection automatically.