gistfile1.txt

console.time('fast array');

var myClass = function() {
  this.array_one = [1,2,3,4,5];
  this.array_two = [1,2,3,4,5];
  this.total = 0;
}

var my_instance = new myClass();

for (var i=0; i < 4; i++) {
   my_instance.total += my_instance.array_one[i];
}
for (var i=0; i < 4; i++) {
   my_instance.total += my_instance.array_two[i];
}

console.timeEnd('fast array');