Maximizing Server Resources

So currently I have two of my apps hosted by RimuHosting. They're on the MiroVPS2 plans which give us 160MB of RAM. I already have a DreamHost account, so instead of running MySQL servers on each VPS, I make them connect to databases hosted by DH. This frees up a good amount of memory and doesn't seem to affect the speed much.

With the freed RAM, I'm able to run three Mongrel instances behind an Apache load balancer. All in all, this provides pretty good throughput.

But I want more! In reality, we're not running into any problems with the current setup. But we're about to release a Facebook app, and if it goes viral I want to keep up with demand. I haven't really made any more modifications, but I've been looking into ways to squeeze the most performance out of our little VPS'. And I came across Swifttiply. It's a clustering proxy server whose main selling point is that it maintains a persistent connection with the backend processes. This cuts down on the socket setup and teardown costs. According to the benchmarks on the website, it seems to really speed things up if you have many concurrent connections.

But I won't convert. Not yet, however. Whenever something new like this comes out, I like to let things settle and see which setup comes out on top. HAProxy is another alternative. Which is better? What combination maximizes throughput? I'm not quite sure. Luckily I'm not pressured to decide at the moment. But I'll keep my ear to the ground to see how best to maximize my server's resources.