We\'re in the process of writing a high-performance server for processing messages. We\'ve been using Jetty for several years and like it, but Netty looks like it has some c
Jetty has had support for asynchronous request processing since version 6 (see here), using a proprietary API. More recent versions support the asynchronous API as part of the Servlet 3.0 API, like any other compliant implementation.
Using Netty would seem like a lot of work for little gain, unless you have highly specific requirements. Otherwise, Jetty would do the job for you with minimal effort.