Run results for: Object vs Map delete and lookup

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:123.0) Gecko/20100101 Firefox/123.0

Browser: Firefox 123

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Object delete

1K/s

Map delete

1K/s

Object lookup

562/s

Map lookup

382/s

View exact numbers

Test name	Executions per second
✓ Object delete	1,461 Ops/sec
Map delete	1,448 Ops/sec
Object lookup	562 Ops/sec
Map lookup	382 Ops/sec

Script Preparation code:

window.map = new Map();
window.obj = {};

for (let i = 0; i < 10000; ++i) {
  window.map.set(i, i);
   window.obj[i] = i;
}

 window.result = undefined;

Tests:

Map lookup
for (let i = 0; i < 10000; ++i) { window.result = window.map.get(i) }
Object lookup
for (let i = 0; i < 10000; ++i) { window.result = window.obj[i]; }
Map delete
const mapCopy = new Map(window.map); for (let i = 0; i < 10000; ++i) { mapCopy.delete(i); }
Object delete
const objCopy = { ... window.obj }; for (let i = 0; i < 10000; ++i) { delete objCopy[i]; }