How do you do Load Testing and Capacity Planning for Web Sites
I've seen tutorials saying they can run decent websites on 64MB RAM (Debian/Lighttpd/PHP/MySQL) however it's not clearly defined how much hits/traffic a "decent" site gets.
Is there a rule of thumb on how much RAM a web server needs? To keep things simple, let's say you're running a site with static content and it's averaging at 100,000 hits per hour (HTML + images combined, no MySQL). How much RAM is the minimum requirement for that?