[Dylan16807]

I'm pretty sure that was supposed to be a list of steps, not a list of options.

> The kernel and your other processes need some space to malloc, and you dont want to page in/out.

Some space, like "most of 20-50 gigabytes"?

You want to take into account how exactly the space used by joins will fit into memory, but 2-5% of a terabyte is an extremely generous allocation for everything else on the box.