More often than not, we have customers indexing fields in Elasticsearch "just in case" they need to be used for search. If that is the case for you, then the following techniques should prove to be valuable in helping you cut costs and focus your cluster performance on what really matters.

Additional References:

• 3 ways to prevent mapping explosion: https://www.elastic.co/blog/3-ways-to-prevent-mapping-explosion-in-elasticsearch