title: How to effectively merge two directories in Emacs?
body: <p>I've tried to use plain <code>ediff-directories</code> to make a diff between files but this is very slow because I need to compare files on every nesting level and there are too many of them.</p>
  
  <p>I've also tried <code>ediff-trees</code> (defined in <a href="http://www.emacswiki.org/emacs/ediff-trees.el" rel="nofollow"><code>ediff-trees.el</code></a>) but that is not convenient either because I don't even see how many files are different and cannot see the picture in general.</p>
  
  <p>Is there another way to do this?</p>