I have been using painless saved on my ES cluster for a while now on a project and little is really documented as far as how it works "under the covers" of elastic search -- at least I can't find much. Can any of the experts tell me:
- How is a Painless script executed on an ES cluster once a query is received? That is, how is it executed differently than using a query?
- Does sharding have a similar impact to performance for Painless scripts as ES queries?
- Are Painless scripts executed in a multithreaded fashion?
- What may be some best practices when using Painless?
- Are there some field types stored on an ES cluster that work better with painless (e.g. keyword vs. integer)?
Thanks in advance.