Caching not increasing performance

When enabling caching inside a query there is a small decrease in performance without any benefit.

sample query:

query: bool: must_have: [term: gender: 'M']

40 shards, 5 million documents, 200 million child documents not part of this query(not sure if relevant).

10 servers, CPU load is very low, 30 gigs of ram each with 15 allocated to heap.

How do I go about debugging something like this?

Thanks!

i can not help you with the cache but you can try to use "filters" / filter bitset to improve your performance !

I am using filters with bitsets