title: Why would I choose a threaded/process-based approach vs. asynchronous web server
body: <p>As I've done some more research into web server software, I've begun to question if Apache's thread/process based method is the way to go vs. the the asynchronous request handling provided by servers like Nginx a Lighttpd, which tend to scale better with heavier loads.</p>
  
  <p>I understand there are many other differences between these latter two and Apache. My question is under what circumstances would I pick a thread/process based method over the asynchronous handling.</p>
  
  <ol>
  <li><p>Are there any features/technologies that I can't use with an asynchronous method (or would function poorly/not as well)?</p></li>
  <li><p>What situations would cause the performance of an asynchronous method to perform worse than a thread/process based approach? Are these common or rare cases, and how big is the difference?</p></li>
  <li><p>Are there any other factors I should take into consideration when comparing the two? Keep in mind I'm focusing mainly on the thread/process based method vs. asynchronous, not any particular server software which happens to utilize one of these methods. These concerns might be difficulty of managing/debugging, security issues, etc.</p></li>
  </ol>