Run results for: copy ArrayBuffer: Uint8Array.set vs by bytes

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 18_4 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/118.0.5993.92 Mobile/15E148 Safari/604.1

Browser: Chrome Mobile iOS 118

Operating system: iOS 18.4

Device Platform: Mobile

Date tested: one year ago

Uint8Array by byte

423.0M/s

Uint8Array with set

868K/s

View exact numbers

Test name	Executions per second
✓ Uint8Array by byte	423,018,720 Ops/sec
Uint8Array with set	868,311 Ops/sec

Script Preparation code:

var size = 0xFFFF;

var source = new Uint8Array(size);
var target = new Uint8Array(size);

for (let i = 0; i < size; i++) {
	source[i] = 100*Math.random();
}

Tests:

Uint8Array by byte
for (let i; i < size; i++) { target[i] = source[i]; }
Uint8Array with set
target.set(source);