You'd think. Write a web server in C and a web server in python/erlang/go/node.js. You'll notice that the one written in C (or C++) runs twice as fast. If it w

You'd think. Write a web server in C and a web server in python/erlang/go/node.js. You'll notice that the one written in C (or C++) runs twice as fast. If it was a syscall bottleneck then they'd achieve the same performance. zero-copy request handling is not possible in high level languages without hacking. For a quick test, run httperf against the dumbest node.js web server that returns 204. Then run the same test against an nginx server that does nothing but return a 204 location / { return 204; } Compare the difference.