[rpedela]

You don't actually need 64GB or 32GB or whatever RAM. The docs should be more clear. What they mean to say is if you have a large enough dataset in production, 64GB RAM per node is the ideal maximum size. That is because 32GB is the max Java heap size that uses 32-bit pointers. So 32GB for Java heap and 32GB for everything else. Although more RAM is generally better because the OS cache will still be utilized making queries faster overall.

I think ES's Java heap default is 1 or 2 GB, and that is more than enough for many use cases. Heap-heavy operations like sorting and aggregations may need more RAM depending on the index size. As far as I know, search isn't heap-heavy so you only need more RAM as query volume increases or index size increases.

For crashes, what version? Version 6.x has never crashed on me, but previous versions did have a tendency to crash for me.