error

$ ember server
version: 0.2.7
Could not find watchman, falling back to NodeWatcher for file system events.
Visit http://www.ember-cli.com/#watchman for more info.
Livereload server on port 35729
Serving on http://localhost:4200/
2015-07-01 10:40 ember[10544] (CarbonCore.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-21)
events.js:85
      throw er; // Unhandled 'error' event
            ^
Error: watch EMFILE
    at exports._errnoException (util.js:746:11)
    at FSEvent.FSWatcher._handle.onchange (fs.js:1157:26)