Script Preparation code:
AخA
 
let array2D = [];
const n = 1000;
const c = 100;
for (let i = 0; i < n; i++) {
  let array1D = [];
  for (let k = 0; k < c; k++) {
    array1D.push(k); 
  }
  array2D.push(array1D);
}
window.array2D = array2D;
Tests:
  • Spreading + concat

     
    let result1 = [].concat(...window.array2D);
  • Flat

     
    let result = window.array2D.flat();
Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Experimental features:

  • Test case name Result
    Spreading + concat
    Flat

    Fastest: N/A

    Slowest: N/A

Latest run results:
Run details: (Test run date: 4 years ago)
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/85.0.4183.102 Safari/537.36 Edg/85.0.564.51
Chrome 85 on Mac OS X 10.13.6
View result in a separate tab
Test name Executions per second
Spreading + concat 5829.9 Ops/sec
Flat 81.5 Ops/sec