Run results for: empty an array in JavaScript?

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 9_3_5 like Mac OS X) AppleWebKit/601.1.46 (KHTML, like Gecko) Version/9.0 Mobile/13G36 Safari/601.1

Browser: Mobile Safari 9

Operating system: iOS 9.3.5

Device Platform: iPhone

Date tested: 7 years ago

Tests:

Just instantiate new array
var size = 10000; var arr1 = []; for (var i = 0; i < size; i++){ arr1.push(i); } arr1 = [];
Set length to zero
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, arr3.length);
Pop all values
var size = 10000; var arr4 = []; for (var i = 0; i < size; i++){ arr4.push(i); } while(arr4.length > 0){ arr4.pop(); }