When compared with WCF, we can be proud that our little mORMot has a very good responsiveness, in regard to all the resources put by Microsoft for optimizing their platform.
"Native" compilation like Delphi can do wonders, when used properly, as we try to do with our framework.

In fact, WCF and mORMot uses the same kernel-mode server of Windows, i.e. http.sys.
See this blog article.

So you can still have "managed" applications (like Java or .Net) be more responsive than "native" applications, when performance was not part of the roadmap, just like with DataSnap.

Some benchmark drawings, extracted from the blog article:

In fact, mORMot did only use 50% of the Server side - the bottleneck on this test was the Client.
With a better client, we may have reached even better results!

Feedback welcome on our forum, as usual.