I'm new to Elasticsearch and I'm wondering as to how many documents I can have in a single index. I'm looking to have around 60-120 million documents of a single type in a single index. Are the documents stored in the disk?
While we're at it, as per what I've read in the documentation, I should not allocate more than 1/4 of my RAM to Elasticsearch. When does Elasticsearch use the RAM? While querying? If so, would having 2-3 nodes in the same cluster help during memory intensive processes?