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It is possible to achieve scalability of a CXF client and service using Spring JMS functionality and the CXF JMS Configuration Feature.
It is not necessary to write any line of code, just configure and leverage already existing stuff.
Using this feature can have essential invluence on the performance for some environments: in one Prove Of Concept I have improved CXF service throughput on 360% (from 500 to 1800 msg/sec) just using session pool and multithread JMS consumer!
Reference performance numbers for SOAP over JMS are represented in Christian Schneider's article: http://www.liquid-reality.de/pages/viewpage.action?pageId=5865562
, so you can easily compare it with own results and make appropriate tunning if necessary.
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