[sehugg]

I would also be interested in the internals. I'd expect JS + a small C event loop to outperform compiled JVM code + lots of async Java I/O libs (for a micro benchmark, at least).

But there's no question Netty is fast even on a non-benchmark. I'm using it for a long-polling server with upwards of 100K connections, and my CPU doesn't go much over 5%. Besides memory usage, the main limitation has been proper kernel configuration.

[joncooper]

I was surprised. We built 'hellod' servers in numerous languages and with various runtime stacks[1]. The results are here and might surprise you:

https://github.com/carbonfive/hellod/blob/master/results.md

[1] C/libev, Clojure/Aleph, Clojure/Jetty, Erlang, Go, Java/Netty, Java/NIO, node.js, JRuby, MRI Ruby