Performance of Array vs. Object

JavaScript performance comparison

Revision 53 of this test case created

Info

After seeing http://jsperf.com/javascript-associative-vs-non-associative-arrays, I thought the test could be improved.

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    var arr = [],
      i,
      obj = {},
      typedArr = [],
      objectClass;
    objectClass = function(payload) {
      this.payload = payload;
    }
    for (i = 0; i < 10000; i += 1) {
      var o = {
        payload: i
      };
      arr.push(o);
      obj[i] = o;
      typedArr.push(new objectClass(i));
    }
};
</script>

Test runner

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Java applet disabled.

Testing in unknown unknown
Test Ops/sec
Array Performance
var sum = 0;
for (var x = 0; x < arr.length; ++x) {
  sum += arr[x].payload
}
pending…
Object Performance
var sum = 0;
for (var x in obj) {
  sum += obj[x].payload;
}
pending…
Object Performance using known length
var sum = 0;
for (var x = 0; x < 10000; ++x) {
  sum += obj[x].payload
}
pending…
Using Object.keys()
var sum = 0;
var keys = Object.keys(obj);
for (var x = 0; x < keys.length; ++x) {
  sum += obj[keys[x]].payload
}
pending…
Array Performance known length
var sum = 0;
for (var x = 0; x < 10000; ++x) {
  sum += arr[x].payload
}
pending…
forEach
var sum = 0;
arr.forEach(function(p) {
  sum += p.payload;
});
pending…
typedArray
var sum = 0;
var i, l;
for (i = 0, l = typedArr.length; i != l; i++) {
  sum += typedArr[i].payload;
}
pending…

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Revisions

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