anchor.diff:  extensions to look at since elasticsearch performs random access on them.
   
   A wildcard can be used in order to indicate that all files should be preloaded:
  -`index.store.pre_load: ["*"]`. Note however that it is generally not useful to
  +`index.store.preload: ["*"]`. Note however that it is generally not useful to
   load all files into memory, in particular those for stored fields and term
   vectors, so a better option might be to set it to
   `["nvd", "dvd", "tim", "doc", "dim"]`, which will preload norms, doc values,
  
positive.code: PUT /my_index
  {
    "settings": {
      "index.store.pre_load": ["nvd", "dvd"]
    }
  }
  ---------------------------------
  
negative.code: This setting is best-effort only and may not work at all depending on the store
  type and host operating system.
  
  The `index.store.preload` is a static setting that can either be set in the
  `config/elasticsearch.yml`:
  
  [source,yaml]
  ---------------------------------
  index.store.preload: ["nvd", "dvd"]
  ---------------------------------
  
  or in the index settings at index creation time:
  