This week's book giveaway is in the Cloud/Virtualization forum. We're giving away four copies of Learning OpenStack Networking: Build a solid foundation in virtual networking technologies for OpenStack-based clouds and have James Denton on-line! See this thread for details.
Basically - and as far as I know - WorkManagers are a mean Ibm introduced to allow a certain degree of parallelism within Java EE components (such as
servlets, EJBs), since it' strongly descouraged usage of spawned threads within a Java EE context.
With recent WAS 8.5.x and support for EJB 3.1 with parallelism required by the specification via @Asynchronous annotation, I think you'll need no longer
to use WorkManagers, even if I suppose they're still used under the hood to implement actually parallelism and asynchronism.
For example, I suggest you to search for example on IBM website.