There’s been sort of a website hosting arms race in the last few years, and a lot of website hosts are constantly making bigger and bigger promises about the amount of resources such as disk memory and bandwidth they can provide.
Eventually, the numbers became sort of silly. Many hosts began offering bandwidth levels that would be practically impossible to provide without melting down the server’s processors and RAM from over-use.
So, can you run a forum with 100,000 active users on an unlimited shared hosting account? Absolutely not! While the disk storage and bandwidth required could probably be handled, that many active users dynamically editing database information would surely bog down the processors and lead to a reduction in response time not just for your own forum but for everyone else who has been hosted on that machine.
But I paid for unlimited bandwidth! That’s true, you can also go to an all-you-can-eat buffet but I bet they will stop you before you eat every piece and crumb of food inside the restaurant.
So what’s the “general” rule of thumb? Don’t do anything that interferes with your neighbor’s ability to run his own websites. Keep your code cleaned up, and cache what you can. Don’t try to put a site with thousands of daily visitors every day on a shared host, and if you do please don’t complain when they suspend the account!
Some hosts are participating with the unlimited hosting marketing campaigns, but taking a humorous approach. Dreamhost is now offering “Unlimited +50GB!” and they’re offering it tongue-in-cheek like it was “infinity plus one!!!111!!eleven!”
Just make sure to read the details in the Terms of Service (TOS), read the hosting reviews, and don’t jump at the first provider who makes an incredibly generous offer!