ES6 Map vs Object properties (v34)

Revision 34 of this benchmark created on

Description

Compare native Map implementation vs using an object as a hash map. Added 2 optimized tests for iterating the hash map.

Preparation HTML

<script>
function randomString()
{
    var text = "";
    var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";

    for( var i=0; i < 5; i++ )
        text += possible.charAt(Math.floor(Math.random() * possible.length));

    return text;
}
</script>

Setup

var map = new Map();
    var obj = Object.create(null);
    
    var map2 = new Map();
    var obj2 = Object.create(null);
    var _keys = [];
    
    for (var i=0; i < 1000; i++) {
       var key = randomString();
       var val = randomString();
       map2.set(key,val);
       obj2[key] = val;
       _keys.push(key);
    }
    
    var pkeys = _keys.map(function(v) {return {
      v: v,
      i: Math.random()
    }}).sort(function(a, b) {return a.i < b.i ? 1 : -1}).map(function(v) {
      return v.v;
    });

Test runner

Ready to run.

Testing in
TestOps/sec
map.set(key,val)
for (var i=0; i < 1000; i++) {
   var key = randomString();
   var val = randomString();
   map.set(key,val);
}
ready
obj[key] = val;
for (var i=0; i < 1000; i++) {
   var key = randomString();
   var val = randomString();
   obj[key] = val;
}
ready
Iterate Map
for (var key of map2.keys()) {
  var val = map2.get(key);
}
ready
Iterate Object
var key;
for (key in Object.keys(obj2)) {
  var val = obj2[key];
}
ready
Iterate Object Keys
var keys = Object.keys(obj2);
for (var i = 0, length = keys.length; i < length; i++) {
    var val = obj2[keys[i]];
}
ready
Iterate Object no hasOwnProperty check
var key;
for (key in obj2) {
    var val = obj2[key];
}
ready
Iterate Object Precomputed Keys
for (var i = 0, length = pkeys.length; i < length; i++) {
    var val = obj2[pkeys[i]];
}
ready
Iterate Map Precomputed Keys
for (var i = 0, length = pkeys.length; i < length; i++) {
    var val = map2.get(pkeys[i]);
}
ready

Revisions

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