Performance of Array vs. Object (v182)

Revision 182 of this benchmark created on

Setup

function makeRandomID() {
    var text = "";
    var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
  
    for (var i = 0; i < 5; i++)
      text += possible.charAt(Math.floor(Math.random() * possible.length));
  
    return text;
  }
  
  
  var arr = [],
    i,
    obj = {},
    randomKeys = [],
    randomObj = {},
    key;
  for (i = 0; i < 10000; i += 1) {
    var o = {
      payload: i
    };
    arr.push(o);
    obj[i] = o;
    key = makeRandomID();
    randomKeys[i] = key;
    randomObj[key] = o;
  }

Test runner

Ready to run.

Testing in
TestOps/sec
Using randomObj
var sum = 0;
for (var x = 0; x < randomKeys.length; ++x) {
  sum += randomObj[randomKeys[x]].payload
}
ready
Array Performance
var sum = 0;
for (var x = 0; x < arr.length; ++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; x < keys.length; ++x) {
  sum += obj[keys[x]].payload
}
ready

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.