When an application developed on webMethods Cloud invokes a service on an on-premise Integration Server, the on-premise Integration Server uses a thread from the server thread pool to process the service request. The processing thread invokes the service, posts the response, and then terminates, which frees up the thread to process other requests. The on-premise Integration Server can process multiple service requests from webMethods Cloud simultaneously.

The watt.server.threadPool.cloudRequests specifies the maximum percentage of the server thread pool that can be used for processing webMethods Cloud requests. The default is 5 which means that if the maximum size of the server thread pool is 1000, up to 50 server threads at a time can be used to process cloud requests.

At start up, Integration Server uses the specified percentage to calculate the number of threads that can be used and logs a message with that information to the server.log. At run-time, when Integration Server reaches the maximum number of threads that can be used to process requests from webMethods Cloud, Integration Server writes the following message and blocks new server requests from webMethods Cloud until a thread becomes available.