A "perfect" ES node has 64 gig of memory. 32 to heap and 32 for off heap as well as 8-12 cores for executing queries. Heap is mostly used for internal operatio

A "perfect" ES node has 64 gig of memory. 32 to heap and 32 for off heap as well as 8-12 cores for executing queries. Heap is mostly used for internal operations and the inverted index stuff (fielddata), off-heap was used for the columnar data store (docvalues). Most server class machines exceed this nowadays, so we would recommend containerizing multiple instances of ES on a single machine and using the rack awareness feature to make sure shards didn't replicate onto the same physical host. It's been a while since I worked at Elastic, so this info might be out of date by now, but we're still using this formula for our ECE setups where I work now.