ElasticSearch query performance

A customer is looking to to get an Elasticsearch response for a very simple query (an exact match on a single field, which returns another field from the matching document) as quickly as possible in under 10 ms.

They ask:

• if a sub 10ms response is possible?
• what the fastest response time they could hope for would be?
• if that is possible, then what changes would we have to make?

What do you think?

Thanks in advance