title: High CPU usage while watching a directory for new files
body: <p>Currently I am using chokidar to watch a directory. The directory has a large amount of files, and it is constantly being written too. I am also using polling because I need to watch folders on a network. I noticed that when I start watching the directory, my CPU usage is really high. </p>
  
  <p>From what I understand, watchers are also being created for each file in the directory? </p>
  
  <p>I only need to be notified if a file has been added, I don't need to monitor for any changes to the file itself. So I feel like there is a lot of overhead being created for what I need. Is this possible with chokidar in any way? Or should I look for another solution for these needs.</p>
  
  <p>Updated:
  Added a snippet of how I am creating my watcher instance. I'm not really doing anything special. I noticed that the CPU usage spikes really high as soon I create the watcher. The directory has about 20k files in it.</p>
  
  <pre><code>var fileWatcher = chokidar.watch('path to directory', {
    ignored: '*.txt',
    ignoreInitial: true,
    usePolling: true,
    interval: 600,
    depth: 0});
  
  fileWatcher.on('add', function(path) {
    //Do something when a new file is created in the watched directory
  });
  </code></pre>