When an enterprise server instance is created it contains two service execution processes (SEPs). SEPs process incoming client requests. When a response has been returned to a client, the SEP becomes available again to handle another request. If all the SEPs are busy handling requests, incoming requests must wait for one to become free. The number of SEPs in an enterprise server instance impacts performance. The kind of impact depends on a number of variables. You will need to experiment to find out the optimum number of SEPs in any particular enterprise server. For more advice see the section Performance Considerations .
You can change the number of SEPs 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 SEPs reverts to the value you set when you added the server or edited the server details.