Run results for: copy ArrayBuffer: DataView vs Uint8Array.set vs Float64Array.set vs by bytes

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.1.2 Safari/605.1.15

Browser: Safari 14

Operating system: Mac OS X 10.14.6

Device Platform: Desktop

Date tested: one year ago

DataView

342.6M/s

Uint8Array by byte

322.0M/s

Uint8Array with set

416K/s

with Float64Array

383K/s

View exact numbers

Test name	Executions per second
✓ DataView	342,603,328 Ops/sec
Uint8Array by byte	322,038,048 Ops/sec
Uint8Array with set	416,236 Ops/sec
with Float64Array	383,166 Ops/sec

Script Preparation code:

var size = 0xFFFF;
var buf = new ArrayBuffer(size);
var view = new DataView(buf);
var byte = new Uint8Array(buf);

var data = new Uint8Array(size);

for (let i = 0; i < size; i++) {
	data[i] = 100*Math.random();
}

Tests:

DataView
for (let i; i < size; i++) { view.setUint8(i, data[i]); }
Uint8Array by byte
for (let i; i < size; i++) { byte[i] = data[i]; }
Uint8Array with set
byte.set(data);
with Float64Array
(new Float64Array(buf, 0, size/8)) .set(new Float64Array(data.buffer, 0, size/8));