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_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.36

Browser: Chrome 128

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Uint8Array by byte

12.0M/s

DataView

10.5M/s

Uint8Array with set

538K/s

with Float64Array

471K/s

View exact numbers

Test name	Executions per second
✓ Uint8Array by byte	11,998,835 Ops/sec
DataView	10,461,013 Ops/sec
Uint8Array with set	537,969 Ops/sec
with Float64Array	470,732 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));