The maximum call stack size

[2014-04-10] esnext, dev, javascript
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Are you curious how many recursive calls you can make on your JavaScript engine?

How many recursive calls?

The following function lets you find out (inspired by a gist by Ben Alman).
    function computeMaxCallStackSize() {
        try {
            return 1 + computeMaxCallStackSize();
        } catch (e) {
            // Call stack overflow
            return 1;
Three results:
  • Node.js: 11034
  • Firefox: 50994
  • Chrome: 10402
What does this number mean? Mr. Aleph pointed out to me that on V8, the number of recursive calls you can make depends on two quantities: the size of the stack and the size of the stack frame (holding parameters and local variables). You can verify the latter by adding local variables to computeMaxCallStackSize() – it’ll return a lower number.

Tail call optimization in ECMAScript 6

ECMAScript 6 will have tail call optimization: If a function call is the last action in a function, it is handled via a “jump”, not via a “subroutine call”. That means that, if you slightly rewrote computeMaxCallStackSize(), it would run forever under ECMAScript 6 (in strict mode):
    function computeMaxCallStackSize(size) {
        size = size || 1;
        return computeMaxCallStackSize(size + 1);