title: How to gather disk usage on a storage system faster than just using "du"?
body: <p>I operates a Synology NAS device and the unit includes that over 600 users data.</p>
  
  <p>The users backup data are tax accounting data.
  So, approximately one user's folder has 200,000 files.</p>
  
  <p>I have to provide their backup data usage informations to each users, but since there are so many directories and files, the <code>du</code> command takes too long to execute.</p>
  
  <p>Could someone provide me a way to check each user's disk usage in a faster way?</p>