Run results for: Object Indexed Properties (Read)

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.116 Safari/537.36

Browser: Chrome 53

Operating system: Mac OS X 10.11.6

Device Platform: Other

Date tested: 8 years ago

Test name	Executions per second
Array	1200.4 Ops/sec
Object	1192.4 Ops/sec
Sparse Array	1096.4 Ops/sec
Sparse Object	1120.1 Ops/sec

Script Preparation code:

var LIMIT = 10000;

var ARRAY = [];
var OBJECT = {};
var SPARSE_ARRAY = [];
var SPARSE_OBJECT = {};

for (var i = 0; i < LIMIT; i++) {
  ARRAY[i] = i;
  OBJECT[i] = i;
  if (i % 2 === 0) {
    SPARSE_ARRAY[i] = i;
    SPARSE_OBJECT[i] = i;
  }
}

Tests:

Array
var total = 0; var target = ARRAY; for (var i = 0; i < LIMIT; i++) { total += target[i]; } return total;
Object
var total = 0; var target = OBJECT; for (var i = 0; i < LIMIT; i++) { total += target[i]; } return total;
Sparse Array
var total = 0; var target = SPARSE_ARRAY; for (var i = 0; i < LIMIT; i++) { if (i in target) { total += target[i]; } } return total;
Sparse Object
var total = 0; var target = SPARSE_OBJECT; for (var i = 0; i < LIMIT; i++) { if (i in target) { total += target[i]; } } return total;

Run results for: Object Indexed Properties (Read)

Array

Object

Sparse Array

Sparse Object