Run results for: Does presetting the size of an array make a difference?

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4033.0 Safari/537.36 Edg/81.0.403.1

Browser: Chrome 81

Operating system: Windows

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
Dynamic	987.5 Ops/sec
Preset	1046.5 Ops/sec

Script Preparation code:

var size = 10000;

Tests:

Dynamic
const arr = []; for (let i = 0; i < size; i++) { arr[i] = i; }
Preset
const arr = new Array(size); for (let i = 0; i < size; i++) { arr[i] = i; }