When do you start additional Elasticsearch nodes?
I'm in the middle of attempting to replace a Solr setup with Elasticsearch. This is a new setup, which has not yet seen production, so I have lots of room to fiddle with things and get them working well. I have very, very large amounts of data. I'm indexing some live data and holding onto it for 7 days (by using the _ttl field). I do not store any data in the index (and disabled the _source field). I expect my index to stabilize around 20 billion rows. I will be putting this data into 2-3 named indexes. Search performance so far with up to a few billion rows is totally acceptable, but indexing