Shay indicated here that routing will always resolve to a single shard.
So, is ES maintaining an internal "index" (by "index", i mean someway of identifying the specific shard for a specific routing id)?
ES would need to somehow map a specific routing id to a specific shard, I would presume.
If so, is there an overhead of maintaining such a relationship? (from memory used and insertion time standpoint)? For e.g., What is the overhead in how ES processes a document coming in without needing a routing would VS a document coming in needing a specific routing?
Thanks in advance for responses,
Elan.