Run results for: Buffer Access 4 - PK

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:97.0) Gecko/20100101 Firefox/97.0

Browser: Firefox 97

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
DataView AoS	203.8 Ops/sec
DataView byte-aligned AoS	195.9 Ops/sec
TypedArray byte-aligned AoS	207.9 Ops/sec
TypeArray SoA	338.7 Ops/sec

Script Preparation code:

var bench1buffer;
var bench2buffer;
var bench3buffer;
var size = 1_000_000;
{
    const stride = 18;
    bench1buffer = new ArrayBuffer(stride * size);
    /*
      0 u16 id
      2 f64 x
      10 f64 y
    */
    for (let i = 0; i < size; i++) {
        const struct = new DataView(bench1buffer, i * stride, stride);
        struct.setUint16(0, i, true);
        struct.setFloat64(2, i, true);
        struct.setFloat64(10, i * 2, true);
    }
}
{
    const stride = 24;
    bench2buffer = new ArrayBuffer(stride * size);
    /*
      0 u16 id
      8 f64 x
      16 f64 y
    */
    for (let i = 0; i < size; i++) {
        const struct = new DataView(bench2buffer, i * stride, stride);
        struct.setUint16(0, i, true);
        struct.setFloat64(8, i, true);
        struct.setFloat64(16, i * 2, true);
    }
}
{
    bench3buffer = {
        id: new Uint16Array(size),
        x: new Float64Array(size),
        y: new Float64Array(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 = 18; /* 0 u16 id 2 f64 x 10 f64 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.getFloat64(offset + 2, true); const y = view.getFloat64(offset + 10, true); sum += id + x * y; } console.log(1, sum);
DataView byte-aligned AoS
const stride = 24; /* 0 u16 id 8 f64 x 16 f64 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.getFloat64(offset + 8, true); const y = view.getFloat64(offset + 16, true); sum += id + x * y; } console.log(2, sum);
TypedArray byte-aligned AoS
const stride = 24; /* 0 u16 id 8 f64 x 16 f64 y */ const f64s = new Float64Array(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 = f64s[offset / 8 + 1]; const y = f64s[offset / 8 + 2]; sum += id + x * y; } console.log(3, sum);
TypeArray SoA
let sum = 0; const idbuf = bench3buffer.id; const xbuf = bench3buffer.x; const ybuf = bench3buffer.y; for (let i = 0; i < size; i++) { const id = idbuf[i]; const x = xbuf[i]; const y = ybuf[i]; sum += id + x * y; } console.log(4, sum);

Run results for: Buffer Access 4 - PK

DataView AoS

DataView byte-aligned AoS

TypedArray byte-aligned AoS

TypeArray SoA