When an enterprise server is created it contains two service execution processes (see the figure Components of a Service Execution Process in the section Service Execution Processes in the chapter Introduction). These handle incoming client requests. When a response has been returned to a client, the service execution process becomes available again to handle another request. If all the service execution processes are busy handling requests, incoming requests have to wait for one to become free. The number of service execution processes in an enterprise server impacts performance. The kind of impact depends on a number of variables. You will need to experiment to find out the optimum number of service execution processes in any particular enterprise server. For more advice see the section Performance Considerations .
You can change the number of service execution processes in an enterprise server while it is running, although any change you make has an effect only until you stop the server. At this point the number of service execution processes reverts to the value you set when you added the server or edited the server details.