Performance drop in EJB server-to-server invocation scenario

Server-to-server EJB invocations exhibit worse performance in EAP 7 compared to EAP 6.
(Conversely, standalone-client-to-server scenario seems to be better than in EAP 6).
See https://mojo.redhat.com/docs/DOC-1057817 for performance test report. Performance team saw a similar difference in SpecJEnterprise test runs.