The code is, but the infra around it was, until recently, pretty slow (and scaled poorly). They can also take advantage of the optimisations in the tcp/ip stack that you get on the linuxes now that it's cross platform :)

its mostly web server benchmark (Kestrel in .net case). So receiving bytes by OS kernel driver, passing them to http server, then to the app, app replies with simple response. Not so relevant to most of us IMHO, since our app code is like 10000x slower than web server can handle, but nice to see .net in first 10:) By looking at computation speed (chess engine?), i would say c# beats Js easily there (should be on-par with Java, but Java has some neat tricks in JIT and can be faster in same cases).

But definitely new .net core feels so much snappier than full fx. Im currently porting few apps (they are simple, no big libs), and so far everything works fine. It took me awhile to catch up with MS changes, since they're iterating little bit to fast... Using full vs 2015 update 2 + r#, and little bit of vs code on ubuntu (r# is still huge productivity booster, i can't switch to vs code yet). Also waiting for Jetbrains Rider, which will bring r# to all platforms!

technically node and v8 JIT compile JS so the JS is also 'compiled'