Run results for: .unshift() vs .push() + .reverse()

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:121.0) Gecko/20100101 Firefox/121.0

Browser: Firefox 121

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: 2 years ago

Benchmark engine: Benchmark.js

.push() + reverse()

3.9M/s

.unshift()

460K/s

View exact numbers

Test name	Executions per second
✓ .push() + reverse()	3,861,102 Ops/sec
.unshift()	459,983 Ops/sec

Script Preparation code:

window.ELE_PER_CYCLE = 100;

Tests:

.unshift()
const reps = window.ELE_PER_CYCLE; const arr = []; for (let i = 0; i < reps; ++i) { arr.unshift(i); }
.push() + reverse()
const reps = window.ELE_PER_CYCLE; const arr = []; for (let i = 0; i < reps; ++i) { arr.push(i); } arr.reverse();