Elasticsearch Optimization: _all

[reissmann]

Do we need to store the _all field? If all queries are executed on a specific field of the mapped documents, storing _all should not be neccessary, which allows us to reduce the size of the index by up to 30%.

[reissmann]

More info: http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/mapping-all-field.html