Run results for: Map() vs Object() on write and read

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:121.0) Gecko/20100101 Firefox/121.0

Browser: Firefox 121

Operating system: Linux

Device Platform: Desktop

Date tested: 2 years ago

Object Iteration

67/s

Map

25/s

View exact numbers

Test name	Executions per second
✓ Object Iteration	67 Ops/sec
Map	25 Ops/sec

Script Preparation code:

function filter(v) {
  return v % 2
}

Tests:

Map
const test = new Map() for (var i=10000; i > 0; i--) { test.set(`key${i}`, i) } for (var i=100; i > 0; i--) { Array.from(test.values()).filter(filter) }
Object Iteration
const test = {} for (var i=10000; i > 0; i--) { test[`key${i}`] = i } for (var i=100; i > 0; i--) { const values = []; for (const id in test) { const value = test[id]; if (filter(value)) { values.push(value); } } }