Benchmark: js array perfomance

Script Preparation code:

function generateTestArray() {
  const result = [];
  for (let i = 0; i < 1000000; ++i) {
    result.push({
      a: i,
      b: i / 2,
      r: 0,
    });
  }
  return result;
}

var array = generateTestArray();

Tests:

Array.forEach
array.forEach((x) => { x.r = x.a + x.b; });
for of
for (const obj of array) { obj.r = obj.a + obj.b; }
for <array.length, indexing
for (let i = 0; i < array.length; ++i) { array[i].r = array[i].a + array[i].b; }
for <len, indexing
const len = array.length; for (let i = 0; i < len; ++i) { array[i].r = array[i].a + array[i].b; }
for <array.length, tmp element
for (let i = 0; i < array.length; ++i) { const x = array[i]; x.r = x.a + x.b; }
for <len, tmp element
const len = array.length; for (let i = 0; i < len; ++i) { const x = array[i]; x.r = x.a + x.b; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.forEach
for of
for <array.length, indexing
for <len, indexing
for <array.length, tmp element
for <len, tmp element

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Safari/537.36

Browser/OS: Chrome 91 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Array.forEach	120.6 Ops/sec
for of	515.4 Ops/sec
for <array.length, indexing	6.7 Ops/sec
for <len, indexing	8.8 Ops/sec
for <array.length, tmp element	13.0 Ops/sec
for <len, tmp element	24.2 Ops/sec

js array perfomance (version: 0)

Comparing performance of: Array.forEach vs for of vs for <array.length, indexing vs for <len, indexing vs for <array.length, tmp element vs for <len, tmp element

Created: 2 years ago by: Registered User

Jump to the latest result

Array.forEach

for of

for <array.length, indexing

for <len, indexing

for <array.length, tmp element

for <len, tmp element

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A