Typical suspects involve an overloaded site (big ass poorly optimized images everywhere) and Apache (poorly optimized too) for the most part.
The site could also benefit from using a CDN such as CloudFlare (given that most of us are from Murika I assume and your host's data center is probably somewhere in EU).
Host can also be a big fat potato, though, I assume this forum is hosted on a VPS? I don't know much about Alwaysdata tbh to give my full analysis.
Last ditch would be to reduce PM messages on each page to a fair amount, cause if you have it at a high amount and expect instant transmission Goku speeds, you'll probably need more time in the hyperbolic time chamber.