MeasureThat.net

Run results for: empty an array in JavaScript - splice vs setting length

Based on question on http://stackoverflow.com/questions/1232040/how-do-i-empty-an-array-in-javascript

Go to the benchmark
Run details:
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.0.1 Safari/605.1.15
Safari 18
Mac OS X 10.15.7
Desktop
3 months ago
Test name Executions per second
Set length to zero 41293.1 Ops/sec
Splice 27575.7 Ops/sec
Tests:

  • Set length to zero

    ​x
     
    var size = 10000;
    var arr2 = [];
    for (var i = 0; i < size; i++){
      arr2.push(i);
    }
    ​
    arr2.length = 0;

  • Splice

     
    var size = 10000;
    var arr3 = [];
    for (var i = 0; i < size; i++){
      arr3.push(i);
    }
    ​
    arr3.splice(0);