gregw

As with most open source projects, it's very hard to get a measure of who/how/where/why Jetty is being used a deployed.  Downloads long ago became meaningless with the advent of many available bundling and distribution channels.   The Netcraft Web Survey is one good measure, as it scans the internet and identifies which server sites run. In the results released April 2008, Jetty is identified for 278,501 public server, which is 80% of the market share of our closest "competitor" tomcat. If we exclude unknowns and others catagory, Jetty is currently 12th in the league table of identified servers of all types and closing in on a top 10 ranking .

The tomcat 6 developers have proposed an asynchronous IO extension as their solution for Comet and Ajax push.  I have long argued that asynchronous handling is needed for Servlets (for comet and other use-cases), but that it is very important to make the distinction between asynchronous IO and asynchronous handling of requests. Asynchronous programming is hard and asynchronous IO even harder.  I maintain that asynchronous IO should be implemented by the container and that only asynchronous events should be delivered to an asynchronous servlet. As if to illustrate my point,the example code that tomcat provide for their asynchronous IO contains some classic bugs and inefficiencies that I examine here as they well illustrate why we should be making all efforts possible to encapsulate asynchronous IO below the level of the servlet API.