I’ve just discovered a Unix tool that allows measuring how many requests you can serve per second… called ‘ab’. It is used like this:
ab -n 100 http://www.ambisonia.com/ > index.pre.ab
The conclusion is that I can currently serve 3.24 pages per second. That’s not great. That’s a total of around 7.7 million pages per month (or about 2 million unique visitors per day). Actually, it will be a fraction of that since site useage will not be evenly spread out.
Currently I’m getting around 1800 unique visitors per month, so there’s no hurry. I’ll probably use a product called squid-cache.