anchor.diff:              "fields": ["title"]
           }
       } ]
  -}
  +}'
   --------------------------------------------------
   
   Response:
  
positive.code: 
  [source,js]
  --------------------------------------------------
  $ curl -XPUT 'localhost:9200/_bench/?pretty=true' -d
  '{
      "name": "my_benchmark",
      "competitors": [ {
          "name": "my_competitor",
  
negative.code: 
  [source,js]
  --------------------------------------------------
  $ curl -XPUT 'localhost:9200/_bench/?pretty=true' -d '{
      "name": "my_benchmark",
      "num_executor_nodes": 1,
      "percentiles" : [ 25, 50, 75 ],
  