Ask HN: Node.js memory optimization

Never noticed this before but I recently stated running multiple node processes on my server and each process is eating up bunch of memory. 100+ mb. Is this because node processes do not share resources? What is the best way to combat this? Is the only option to combine all processes into one?

Another question is in regards to modules and memory. If your single node process loads a module that is also loaded inside another module, is the module loaded multiple times? Or is it shared inside a single process?