19.7.1. EJB3 Asynchronous Invocation Service
The Asynchronous Invocation Service is an Enterprise JavaBeans container service that manages asynchronous invocation of session bean methods. This service maintains a configurable number of threads (a thread pool) that are allocated for asynchronous method execution.
Enterprise JavaBeans 3.1 allows for any method of a session bean (stateful, stateless or singleton) to be annotated to permit asynchronous execution.