memory usage

result.sh-session

$ nodejs --version  && lua -v && luajit -v
	v0.10.28
	Lua 5.2.3  Copyright (C) 1994-2013 Lua.org, PUC-Rio
	LuaJIT 2.0.3 -- Copyright (C) 2005-2014 Mike Pall. http://luajit.org/

$ nodejs --expose-gc test.js && lua test.lua && luajit test.lua
	----
	nodejs
	----
	  1804856
	255285256
	177807656
	---
	lua
	---
	    24214
	100687638
	 16799614
	---
	luajit
	---
	    28069
	 58749005
	  4221265

test.js

console.log("----");
console.log(process.argv[0]);
console.log("----");
global.gc();
console.log(process.memoryUsage().heapUsed);
var BIGNUM = Math.pow(2,20);
var a = [];
var b = {};

for (_i = 0; _i < BIGNUM; ++_i) {
	(function(i) {
		a[i] = function(v) {
			return { v : i }
		}
	}(_i));
}
global.gc();
console.log(process.memoryUsage().heapUsed);

for (i = 0; i < BIGNUM; ++i) {
	var key = "KEYOF" + i;
	var tmp = a[i](key);
	b[key] = tmp[key];
}
a = undefined;
global.gc();
console.log(process.memoryUsage().heapUsed);

test.lua

print("---")
print(arg[-1])
print("---")
collectgarbage 'collect'
print(1024 * collectgarbage 'count')
local BIGNUM = math.pow(2,20)
local a, b = {}, {}

for i=1, BIGNUM do
	a[i] = function(v)
		return { v = i }
	end
end
collectgarbage 'collect'
print(1024 * collectgarbage 'count')

for i, f in ipairs(a) do
	local key = "KEYOF" .. tostring(i)
	local tmp = f(key)
	b[key] = tmp[key]
end
a = nil
collectgarbage 'collect'
print(1024 * collectgarbage 'count')