Exactly. Also GWan and Monkey[1] claim that their webserver perform faster while remain lightweight. Anyone interested to put RPi on actual datacenter can do so with EDIS for free[2]

[1]http://gwan.ch/benchmark http://monkey-project.com/benchmarks/raspberry_pi_monkey_ngi...

[2]https://news.ycombinator.com/item?id=4636374

I like hiawatha for low-spec boxes. I run it on a couple of tiny VPSs I have.

http://www.hiawatha-webserver.org/