[damien_ls]

256 is quite low, but with a decent provider that is sensible about bursting (on the assumption that the virtualisation platform in question supports it, and the provider enables it) then it works fine.

It can make a big difference what control panel software you run - cPanel is a bit tight on 256, whilst DirectAdmin and Plesk will run fine on 128 (guarantee).

However, as I think I mentioned earlier - your provider should be able to tell you exactly which resources are hitting limits and causing your problems. Just throwing memory (or anything else) at the problem is a bit silly unless you know for sure that it's the problem...

Script (and/or SQL query) optimisation is one potential way to help; that's coming at the problem from the other end. I.e. you can either use less resources, or increase the amount of resources available - in both cases you end up with enough resources for your needs (hopefully!).

It could just be that the provider is overloading the node and you're not getting a good slice of CPU time etc. so your processes are left queuing hence things build up and so on..