Benchmark: Concat vs spread [...Arr1, ...Arr2] for large arrays

Script Preparation code:

window.top.tests = {control:[], concat:[], spread:[]};
window.test = (new Array(10)).fill(null);
window.cutoff = 5000;

Tests:

Control (for push)
for (let element of window.test) window.top.tests.control.push(element); if (window.top.tests.control.length > window.cutoff) { window.top.tests.control = []; console.log('reset control'); }
Concat
window.top.tests.concat = window.top.tests.concat.concat(window.test); if (window.top.tests.concat.length > window.cutoff) { window.top.tests.concat = []; console.log('reset concat'); }
Spread
window.top.tests.spread = [...window.top.tests.spread, ...window.test]; if (window.top.tests.spread.length > window.cutoff) { window.top.tests.spread = []; console.log('reset spread'); }

Rendered benchmark preparation results:

Previous results

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/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Mac OS X 10.15.7

Concat

1.4M/s

Control (for push)

978K/s

Spread

560K/s

View exact numbers

Concat vs spread [...Arr1, ...Arr2] for large arrays (version: 1)