InfernalH

Already in production for months, no particular problems

I tried with a "pure" Array - for Ruby it's 1Mb for 100 000 elements

EDIT: and for Hash with h[i] = i, it's ~6Mb

Everytime when you try to build bigger app with sinatra, you will probably end up building half-rails. So it the end it doesn't make much sense just the time it was needed to put in to find and require additional libs