Within the next couple of days, I'm going to need two Linux VPS instances (probably Ubuntu 10.04), one running PHP and one for Ruby on Rails. Both are most likely going to use nginx and MySQL and have about 256-512MB RAM.
Now the question is, should I go with a 32bit or 64bit system? There is a related question already posted, but without any specific information on how to decide.
How does 32bit vs 64bit system behave from your experience in these conditions? (Ruby/PHP, nginx, MySQL)
Best Answer
One of the biggest factors to consider when choosing between 32 and 64bit OSs is growth. With a 32bit OS you'll hit the ceiling on performance when you hit 4gb of RAM. With a 64bit OS the performance ceiling is basically whatever your your budget will allow. Judging from what you're describing, unless you're expecting to grow really fast I'd say you're probably fine for a while.