Run results for: Recursion vs Iteration (with tail recursion)

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36

Browser: Chrome 121

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

for loop

6.8M/s

while loop

6.7M/s

recurse (tail)

1.1M/s

recursion

947K/s

View exact numbers

Test name	Executions per second
✓ for loop	6,787,554 Ops/sec
while loop	6,716,113 Ops/sec
recurse (tail)	1,056,807 Ops/sec
recursion	947,384 Ops/sec

Script Preparation code:

  var nums = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
  
  function sum_recurse(arr, i) {
   i = i || 0;
   if (i > arr.length)
     return 0;
   else
     return arr[i] + sum_recurse(arr, i + 1);
  }

 function sum_recurse_tail(arr, i, sum = 0) {
   i = i || 0;
   if (i > arr.length)
     return 0;
   else
     return sum_recurse(arr, i + 1, sum + arr[i]);
  }
  
  function sum_while(arr) {
   var total = 0,
       i = 0,
       len = arr.length;
  
   while (i < len) {
    total += arr[i++];
   }
  
   return total;
  }
  
  function sum_for(arr) {
   var total = 0,
       len = arr.length;
  
   for (var i = 0; i < len; i++) {
    total += arr[i];
   }
  
   return total;
  }

Tests:

recursion
sum_recurse(nums)
while loop
sum_while(nums)
for loop
sum_for(nums)
recurse (tail)
sum_recurse_tail(nums)