luma.gl/test/bench/array-copy.bench.js

// luma.gl, MIT license
// Copyright (c) vis.gl contributors

/* eslint-disable no-console, no-invalid-this */

const LARGE_ARRAY = new Float32Array(1e6);
for (let i = 0; i < 1e6; i++) {
  LARGE_ARRAY[i] = Math.random();
}

const MEDIUM_ARRAY = new Float32Array(1e1);
for (let i = 0; i < 1e1; i++) {
  MEDIUM_ARRAY[i] = Math.random();
}

const SMALL_ARRAY = new Float32Array(1e1);
for (let i = 0; i < 1e1; i++) {
  SMALL_ARRAY[i] = Math.random();
}

// add tests

// Small copies could be overwhelmed by array creation.
const savedNewArray = new Float32Array(1e1);

export default function arrayCopyBench(suite) {
  return suite
    .group('TYPED ARRAY COPY')
    .add('copy#for-loop (1e6 elements)', () => {
      const length = LARGE_ARRAY.length;
      const newArray = new Float32Array(length);
      for (let i = 0; i < length; ++i) {
        newArray[i] = LARGE_ARRAY[i];
      }
    })
    .add('copy#set (1e6 elements)', () => {
      const length = LARGE_ARRAY.length;
      const newArray = new Float32Array(length);
      newArray.set(LARGE_ARRAY);
    })
    .add('copy#for-loop (1e3 elements)', () => {
      const length = MEDIUM_ARRAY.length;
      const newArray = new Float32Array(length);
      for (let i = 0; i < length; ++i) {
        newArray[i] = MEDIUM_ARRAY[i];
      }
    })
    .add('copy#set (1e3 elements)', () => {
      const length = MEDIUM_ARRAY.length;
      const newArray = new Float32Array(length);
      newArray.set(MEDIUM_ARRAY);
    })
    .add('copy#for-loop (10 elements)', () => {
      const length = SMALL_ARRAY.length;
      for (let i = 0; i < length; ++i) {
        savedNewArray[i] = SMALL_ARRAY[i];
      }
    })
    .add('copy#set (10 elements)', () => {
      savedNewArray.set(SMALL_ARRAY);
    })
    .add('check type#instanceof Float32Array', () => {
      return SMALL_ARRAY instanceof Float32Array;
    })
    .add('check type#ArrayBuffer.isView', () => {
      return ArrayBuffer.isView(SMALL_ARRAY);
    });
}