Run results for: Map vs Object - Insertion, Lookup, Update & Deletion

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:139.0) Gecko/20100101 Firefox/139.0

Browser: Firefox 139

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

Object

3/s

Map

2/s

View exact numbers

Test name	Executions per second
✓ Object	3 Ops/sec
Map	2 Ops/sec

Script Preparation code:

const map = new Map();
const obj = {};

const baseKey = '00000000000000000000';

const getKey = (index) => {
  let key = baseKey;

  const chars = [...index.toString()];
  for (let i = 0; i < chars.length; i++) {
    key[i] = chars[i];
  }

  return key;
};

Tests:

Map
// 1: insert, lookup & update for (let i = 0; i < 100000; i++) { const key = getKey(i); map.set(key, 'value'); const _ = map.get(key); map.set(key, 'newValue'); } // 2: delete all keys for (let i = 0; i < 100000; i++) { const key = getKey(i); map.delete(key); } // 3: insert, lookup & update again for (let i = 0; i < 100000; i++) { const key = getKey(i); map.set(key, 'value'); const _ = map.get(key); map.set(key, 'newValue'); }
Object
// 1: insert, lookup & update for (let i = 0; i < 100000; i++) { const key = getKey(i); obj[key] = 'value'; const _ = obj[key]; obj[key] = 'newValue'; } // 2: delete all keys for (let i = 0; i < 100000; i++) { const key = getKey(i); delete obj[key]; } // 3: insert, lookup & update again for (let i = 0; i < 100000; i++) { const key = getKey(i); obj[key] = 'value'; const _ = obj[key]; obj[key] = 'newValue'; }

Run results for: Map vs Object - Insertion, Lookup, Update & Deletion

Insertion, Lookup, Update & Deletion of Map vs Object. Keys length: 20. Loop length: 100000.

Map

Object