Run results for: Buffer Access 4

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/15.3 Safari/605.1.15

Browser: Safari 15

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
DataView AoS	12.8 Ops/sec
DataView byte-aligned AoS	13.3 Ops/sec
TypedArray byte-aligned AoS	13.2 Ops/sec
TypeArray SoA	14.0 Ops/sec

Script Preparation code:

var bench1buffer;
var bench2buffer;
var bench3buffer;
var size = 1_000_000;
{
    const stride = 10;
    bench1buffer = new ArrayBuffer(stride * size);
    /*
      0 u16 id
      2 f32 x
      6 f32 y
    */
    for (let i = 0; i < size; i++) {
        const struct = new DataView(bench1buffer, i * stride, stride);
        struct.setUint16(0, i, true);
        struct.setFloat32(2, i, true);
        struct.setFloat32(6, i * 2, true);
    }
}
{
    const stride = 12;
    bench2buffer = new ArrayBuffer(stride * size);
    /*
      0 u16 id
      4 f32 x
      8 f32 y
    */
    for (let i = 0; i < size; i++) {
        const struct = new DataView(bench2buffer, i * stride, stride);
        struct.setUint16(0, i, true);
        struct.setFloat32(4, i, true);
        struct.setFloat32(8, i * 2, true);
    }
}
{
    bench3buffer = {
        id: new Uint16Array(size),
        x: new Float32Array(size),
        y: new Float32Array(size),
    };
    for (let i = 0; i < size; i++) {
        bench3buffer.id[i] = i;
        bench3buffer.x[i] = i;
        bench3buffer.y[i] = i * 2;
    }
}

Tests:

DataView AoS
const stride = 10; /* 0 u16 id 2 f32 x 6 f32 y */ const view = new DataView(bench1buffer); let sum = 0; for (let i = 0; i < size; i++) { const offset = i * stride; const id = view.getUint16(offset, true); const x = view.getFloat32(offset + 2, true); const y = view.getFloat32(offset + 6, true); sum += id + x * y; } console.log(1, sum);
DataView byte-aligned AoS
const stride = 12; /* 0 u16 id 4 f32 x 8 f32 y */ const view = new DataView(bench2buffer); let sum = 0; for (let i = 0; i < size; i++) { const offset = i * stride; const id = view.getUint16(offset, true); const x = view.getFloat32(offset + 4, true); const y = view.getFloat32(offset + 8, true); sum += id + x * y; } console.log(2, sum);
TypedArray byte-aligned AoS
const stride = 12; /* 0 u16 id 4 f32 x 8 f32 y */ const f32s = new Float32Array(bench2buffer); const u16s = new Uint16Array(bench2buffer); let sum = 0; for (let i = 0; i < size; i++) { const offset = i * stride; const id = u16s[offset / 2]; const x = f32s[offset / 4 + 1]; const y = f32s[offset / 4 + 2]; sum += id + x * y; } console.log(3, sum);
TypeArray SoA
let sum = 0; const ids = bench3buffer.id; const xs = bench3buffer.x; const ys = bench3buffer.y; for (let i = 0; i < size; i++) { const id = ids[i]; const x = xs[i]; const y = ys[i]; sum += id + x * y; } console.log(4, sum);

Run results for: Buffer Access 4

DataView AoS

DataView byte-aligned AoS

TypedArray byte-aligned AoS

TypeArray SoA