Performance of Array vs. Object (v194)

Revision 194 of this benchmark created on

Setup

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

Test runner

Ready to run.

Testing in
TestOps/sec
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
Object.keys with cachedLength and reverse while loop
var sum = 0,
  keys = Object.keys(obj),
  x = keys.length;
while (x--) {
  sum += obj[keys[x]].payload
}
ready
Tracked keys with cachedLength
var sum = 0,
  keysLength = keys.length,
  i;

for(x = 0; x < keysLength; x++) {
  sum += obj[keys[x]].payload
}
ready

Revisions

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