Run results for: Map vs Object (large)

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 14_3 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.0.2 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 14

Operating system: iOS 14.3

Device Platform: Mobile

Date tested: 3 years ago

Test name	Executions per second
Map lookup	580519.8 Ops/sec
Obj lookup	634626.1 Ops/sec

Script Preparation code:

var map = new Map();
var obj = {};
obj['b'] = 5;
delete obj['b'];

for (var x = 0; x < 1000; x++) {
  map.set("x" + x, x);
  obj["x" + x] = x;
}
map.set('a', 5);
obj['a'] = 5;

var i = 0, count = 10, a;

Tests:

Map lookup
for (i = 0; i < count; i++) { a = map.get('a'); }
Obj lookup
for (i = 0; i < count; i++) { a = obj['a']; }

Run results for: Map vs Object (large)

Lookup of map vs object

Map lookup

Obj lookup