> What kind of program requires that much ram?

Elasticsearch is written in Java, and routinely uses 30GB+ of RAM. I suspect if it was written in Python, it would use an order of magnitude more.

I think you are confusing VM with RSS memory metrics. Elasticsearch is not using routinely 30GB+ of RAM, I am using it on machines that have a lot less RAM. You can additionally set how much RAM you want to give to JVM.

It would depend on the data set you want cached in memory I would think? And you set that in a configuration file I suppose. You can probably set it to use 128MB or RAM too.

An in-memory database essentially