node.js - Big performance loss with NodeJS loops on Amazon EC2 server -

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i running amazon ec2 m1 general purpose small (1 core x 1 unit) 64 bit instance.

i've established amazon instance on average half fast computer i'm working on when using single-threaded nodejs app:

var time = date.now();  var fibo = function(n) {   return n == 0 ? 0 :          n == 1 ? 1 :          fibo(n-1) + fibo(n-2); };  console.log("fibo(40) = " + fibo(40));  time = date.now() - time; console.log("took: " + time + " ms");

localhost:
fibo(40) = 102334155
took: 1447 ms

amazon ec2:
fibo(40) = 102334155
took: 3148 ms

now when in bigger app iterate on big 5mb json object (5mb being formatted , indented filesize, assume smaller internally) using 6 nested for loops (and sake of argument please assume me necessary) end 9.000.000 iterations.

on localhost, takes 8 seconds. on amazon ec2, takes 46 seconds.

i expected 20 seconds @ most.

what causes amazon lag more?

i know v8 highly optimized.

is javascript/v8/node.js perhaps using optimizations aren't compatible virtual machines (like ec2 instance)?

and similarly

any special kind of code optimizations recommended crazy stuff this?


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