Benchmark: array push vs reduce

Tests:

array push
const result = []; Object.entries(oldData).forEach(([key, oldValue]) => { const newValue = newData[key]; if (typeof newValue === 'undefined' || oldValue !== newValue) { result.push(key); } });
optimized push
const result = []; Object.keys(oldData).forEach((key) => { if (oldData[key] !== newData[key]) { result.push(key); } });
reduce
const result = Object.entries(oldData).reduce((accum, [key, oldValue]) => { const newValue = newData[key]; if (typeof newValue === 'undefined' || oldValue !== newValue) { return [...accum, key]; } return accum; }, []);
optimized reduce
const result = Object.keys(oldData).reduce((accum, key) => { if (oldData[key] !== newData[key]) { accum.push(key); } return accum; }, []);

Historical Performance Data aggregated from 10 community runs

Desktop Results:

Chrome 10 runs

reduce

4.0M/s

array push

3.3M/s

optimized reduce

3.1M/s

optimized push

2.9M/s

Fastest: reduce (1.4x faster)

View exact numbers

✓ reduce: 4,038,425 ops/sec
• array push: 3,260,239 ops/sec
• optimized reduce: 3,084,779 ops/sec
• optimized push: 2,900,934 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Test case name	Result
array push
optimized push
reduce
optimized reduce

Latest run results:

Run details: (Test run date: 10 months ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/138.0.0.0 YaBrowser/25.8.0.0 Safari/537.36

Browser/OS: Yandex Browser 25 on Linux

View result in a separate tab

optimized reduce

16.0M/s

optimized push

15.6M/s

reduce

11.5M/s

array push

6.2M/s

View exact numbers

Test name	Executions per second
✓ optimized reduce	15,955,691 Ops/sec
optimized push	15,622,759 Ops/sec
reduce	11,509,996 Ops/sec
array push	6,227,792 Ops/sec

array push vs reduce (version: 0) Benchmark.js

Comparing performance of: `array push vs optimized push vs reduce vs optimized reduce`

Created: 3 years ago by: Guest

Go to the latest result

array push

optimized push

reduce

optimized reduce

Historical Performance Data aggregated from 10 community runs

Desktop Results:

Chrome 10 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

array push vs reduce (version: 0) Benchmark.js

Comparing performance of: array push vs optimized push vs reduce vs optimized reduce

Created: 3 years ago by: Guest

Go to the latest result

array push

optimized push

reduce

optimized reduce

Historical Performance Data aggregated from 10 community runs

Desktop Results:

Chrome 10 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Related benchmarks

Comparing performance of: `array push vs optimized push vs reduce vs optimized reduce`