That makes me all the more curious: why is it faster? I cannot imagine Node doing something obviously wrong that would explain the difference. Evented I/O is pretty well understood, I/O loops aren't that hard and it's all just accept()/read()/write()/close() at the end of the day. Where does the 5x difference come from?
Wow, I didn't know that. I certainly did not expect to find that information in the FAQ. In fact this is the first time I've heard of a web server doing that.
So was the benchmark the author posted with microcaching turned on? While it's a legit way to reduce the load in real-world situations, it feels a little like cheating when used in a benchmark.