Broker 10.15 | webMethods Broker Documentation | webMethods Broker Messaging Programmer's Guide | Message Streaming | Size Guidelines
 
Size Guidelines
Consider using the webMethods message streaming feature only when message size is 1 MB or greater; otherwise, use regular messaging.
For messages averaging between 1 MB and 1 GB in size, use CLIENT_ACKNOWLEDGE when creating a session. For messages averaging over 1 GB in size, use AUTO_ACKNOWLEDGE when creating a session.