Run results for: tiny Array.find vs. Map.get

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.36

Browser: Chrome 142

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 8 months ago

Map.get, 5 elements

109.9M/s

Array.find, 5 elements

44.5M/s

Array to Map + Map.get, 1 lookup

9.0M/s

Array to Map + Map.get, 10 lookups

6.3M/s

Array.find, 10 lookups

5.6M/s

Array to Map + Map.get, 100 lookups

1.6M/s

Array.find, 100 lookups

598K/s

View exact numbers

Test name	Executions per second
✓ Map.get, 5 elements	109,855,464 Ops/sec
Array.find, 5 elements	44,489,396 Ops/sec
Array to Map + Map.get, 1 lookup	9,037,089 Ops/sec
Array to Map + Map.get, 10 lookups	6,343,934 Ops/sec
Array.find, 10 lookups	5,616,477 Ops/sec
Array to Map + Map.get, 100 lookups	1,616,143 Ops/sec
Array.find, 100 lookups	597,641 Ops/sec

Script Preparation code:

function getRandomElement(id) {
  return {
    id,
    a: Math.random(),
    b: Math.random(),
    c: Math.random(),
  }
}

function getArray(length) {
  const result = [];
  for (let i = 0; i < length; i++) {
    result.push(getRandomElement(i))
  }
  
  return result;
}

function arrayToMap(array) {
  return new Map(array.map(el => [el.id, el]));
}

function getRandomInt(max) {
  return Math.floor(Math.random() * max);
}

array_small = getArray(5);
array_large = getArray(5);

map_small = arrayToMap(array_small);
map_large = arrayToMap(array_large);

Tests:

Array.find, 5 elements
const target = getRandomInt(4); array_small.find(el => el.id === target);
Map.get, 5 elements
const target = getRandomInt(4); map_small.get(target);
Array to Map + Map.get, 1 lookup
const map = arrayToMap(array_small); const target = getRandomInt(4); map.get(target);
Array to Map + Map.get, 10 lookups
const map = arrayToMap(array_small); for (let i = 0; i < 10; i++) { const target = getRandomInt(4); map.get(target); }
Array to Map + Map.get, 100 lookups
const map = arrayToMap(array_small); for (let i = 0; i < 100; i++) { const target = getRandomInt(4); map.get(target); }
Array.find, 10 lookups
for (let i = 0; i < 10; i++) { const target = getRandomInt(4); array_small.find(el => el.id === target) }
Array.find, 100 lookups
for (let i = 0; i < 100; i++) { const target = getRandomInt(4); array_small.find(el => el.id === target) }