The Server Manager process is used to manage the Method Server processes. The Server Manager starts the configured number of Method Servers, and then monitors those processes. If it finds one of the Method Server processes has crashed, then it will launch a new one to replace it. Though, the main purpose of the Server Manager is to provide cache synchronization between Method Servers. Method Servers retain numerous in memory caches for performance reasons. The Server Manager will maintain the master copy of these caches. Anytime a Method Server process adds or removes a cache entry, the server manager will synchronize this change with all the other Method Server Processes.
The Method Server is the main Windchill process. This is what processes all user requests, and where most of the Windchill code will execute. You can definitely run multiple Method Server processes, in which case Tomcat will load balance incoming user requests between all of the available Method Server processes. Though, if you are running multiple Method Servers, then you will also need to run a Background Method Server process. The Background Method Server only processes the background queues used in Windchill, and does not handle any user requests.
