Benchmark: slice vs moving array vs reduce

Script Preparation code:

var arr = [];
for (var i = 0; i < 100; i++) {
  arr.push(i);
}

Tests:

moving array
var range = []; for (var i = 0; i < arr.length; i++) { range.push(arr[i]); if (range.length > 9) { range.splice(0, 1); } if (i > 8) {var avg = range.reduce(function(accu, next){ return accu + next ;}) / 9;} }
slice
for (var i = 0; i < arr.length; i++) { if (i < 9) continue; var range = arr.slice(i, i + 9); var avg = range.reduce(function(accu, next){ return accu + next ;}) / 9; }
reduce
var sum = 0; for (var i = 0; i < arr.length; i++) { sum += arr[i]; if (i > 8) { sum -= arr[i - 9]; } if (i > 8) {var avg = sum / 9;} }

Historical Performance Data aggregated from 7 community runs

Desktop Results:

Chrome 7 runs

slice

124K/s

reduce

107K/s

moving array

104K/s

Fastest: slice (1.2x faster)

View exact numbers

✓ slice: 123,761 ops/sec
• reduce: 107,301 ops/sec
• moving array: 104,217 ops/sec

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

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
moving array
slice
reduce

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36

Browser/OS: Chrome 134 on Mac OS X 10.15.7

View result in a separate tab

reduce

2.4M/s

slice

371K/s

moving array

236K/s

View exact numbers

Test name	Executions per second
✓ reduce	2,358,785 Ops/sec
slice	370,543 Ops/sec
moving array	236,278 Ops/sec

slice vs moving array vs reduce (version: 9) Benchmark.js

Comparing performance of: `moving array vs slice vs reduce`

Created: 6 years ago by: Registered User

Go to the latest result

moving array

slice

reduce

Historical Performance Data aggregated from 7 community runs

Desktop Results:

Chrome 7 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

slice vs moving array vs reduce (version: 9) Benchmark.js

Comparing performance of: moving array vs slice vs reduce

Created: 6 years ago by: Registered User

Go to the latest result

moving array

slice

reduce

Historical Performance Data aggregated from 7 community runs

Desktop Results:

Chrome 7 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Comparing performance of: `moving array vs slice vs reduce`