anchor.diff:  used by Kudu. For example, the size listed by `ls -l` does not accurately
   reflect the disk space used by Kudu data files:
   
  -[source,bash]
   ----
   $ ls -lh /data/kudu/tserver/data
   total 117M
  
positive.code: block cache, which can be found on the `/metrics` endpoint of the web UI. An
  example set:
  
  [source,json]
  ----
  {
    "name": "block_cache_inserts",
  
negative.code: 
  The `du` and `df` utilities report the actual disk space usage by default.
  
  ----
  $ du -h /data/kudu/tserver/data
  118M   /data/kudu/tserver/data
  