nodejs msgpack is slowsauce.

foo.js

msgpack = require("msgpack-0.4");
msgpack.pack(JSON.parse(require("fs").readFileSync("../var/inputs.json")))

foo.rb

require "rubygems"
require "msgpack"
require "json"

puts MessagePack.pack(JSON.parse(File.read("../var/inputs.json")))

results.md

node is node 0.4.8 with msgpack-0.4 (since 'msgpack is abandoned and fails in node 0.4.x. ruby is ruby 1.8.7

Majority of time spent is in msgpack.pack for nodejs. Input file "inputs.json" is 4.7MB of json:

% du -sh ../var/inputs.json
4.7M    ../var/inputs.json

% time node foo.js 
node foo.js  16.63s user 0.10s system 98% cpu 17.069 total

% time ruby foo.rb
ruby foo.rb  0.29s user 0.05s system 98% cpu 0.341 total