I'm trying to figure out if expensive queries are causing our search queues to back up and have some questions related to how elasticsearch counts threads.
When a search request fans over multiple shards, does it use threads from each node's thread pool?
For example, if I have 10 nodes with 1 shard each (10 shards total) and I do a search request, would this search request be reflected as:
- 10 "active" threads (one for each node/shard)? Or
- 1 "active" thread for the search request?