Performance of Array vs. Object (v45)

Revision 45 of this benchmark created on

Preparation HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.5.2/underscore-min.js"></script><script src="https://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>

Setup

var arr = [],
    i,
    obj = {};
  for (i = 0; i < 10000; i += 1) {
    var o = {
      payload: i
    };
    arr.push(o);
    obj[i] = o;
  }

Test runner

Ready to run.

Testing in
TestOps/sec
Array Performance
var sum = 0;
for (var x = 0, len = arr.length; x < len; ++x) {
  sum += arr[x].payload
}
ready
Object Performance
var sum = 0;
for (var x in obj) {
  sum += obj[x].payload;
}
ready
Object Performance using known length
var sum = 0;
for (var x = 0; x < 10000; ++x) {
  sum += obj[x].payload
}
ready
Using Object.keys()
var sum = 0;
var keys = Object.keys(obj);
for (var x = 0, len = keys.length; x < len; ++x) {
  sum += obj[keys[x]].payload
}
ready
Array in
var sum = 0;
for (var x in arr) {
  sum += x.payload
}
ready
Array using Underscore.js
var sum = 0;
_.each(arr, function(x) {
  sum += x.payload
});
ready
Object using Underscore.js
var sum = 0;
_.each(obj, function(x) {
  sum += x.payload
});
ready
Array with index using jQuery.js
var sum = 0;
$.each(arr, function(x) {
  sum += arr[x];
});
ready
Object with index using jQuery.js
var sum = 0;
$.each(obj, function(x) {
  sum += obj[x].payload;
});
ready

Revisions

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