Run results for: Reading Map vs Object/Record

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:155.0) Gecko/20100101 Firefox/155.0

Browser: Firefox 155

Operating system: Linux

Device Platform: Desktop

Date tested: 9 days ago

Benchmark engine: Benchmark.js

Map

4/s

Object/Record

3/s

View exact numbers

Test name	Executions per second
✓ Map	4 Ops/sec
Object/Record	3 Ops/sec

Script Preparation code:

let map = new Map();
let obj = {};

const ENTRIES = 1000000;
const LOOKUPS = 300000;
const RUNS = 4;

const ids = Array.from({
    length: ENTRIES
}, () => crypto.randomUUID());
const lookupIds = Array.from({
    length: LOOKUPS
}, () => ids[Math.floor(Math.random() * (ENTRIES + 1))]);

for (let i = 0; i < ENTRIES; i++) {
    map.set(ids[i], i);
    obj[ids[i]] = i;
}

Tests:

Map
for (let j = 0; j < RUNS; j++) { let checksum = 0; for (let i = 0; i < LOOKUPS; i++) { checksum += map.get(lookupIds[i]); } console.log(checksum); }
Object/Record
for (let j = 0; j < RUNS; j++) { let checksum = 0; for (let i = 0; i < LOOKUPS; i++) { checksum += obj[lookupIds[i]]; } console.log(checksum); }