Sorting algorithms comparison

This article describes a simple example program that we use in two of the Performance guides: the guide to the Call Tree and the guide to the Flame Chart.

This program compares the performance of three different sorting algorithms:

• bubble sort

• selection sort

• quicksort

It consists of the following functions:

about:debugging	Debug add-ons, content tabs, and workers running in the browser.
sortAll()	Top-level function. Iteratively (200 iterations) generates a randomized array and calls sort().
sort()	Calls each of bubbleSort(), selectionSort(), quickSort() in turn and logs the result.
bubbleSort()	Implements a bubble sort, returning the sorted array.
selectionSort()	Implements a selection sort, returning the sorted array.
quickSort()	Implements quicksort, returning the sorted array.
swap()	Helper function for bubbleSort() and selectionSort().
partition()	Helper function for quickSort().

Its call graph looks like this:

sortAll()                 // (generate random array, then call sort) x 200
  -> sort()               // sort with each algorithm, log the result
    -> bubbleSort()
      -> swap()
    -> selectionSort()
      -> swap()
    -> quickSort()
      -> partition()

The implementations of the sorting algorithms in the program are taken from https://github.com/nzakas/computer-science-in-javascript/ and are used under the MIT license.

You can try out the example program here and clone the code here (be sure to check out the gh-pages branch). You can also download the specific profile we discuss - just import it to the Performance tool if you want to follow along. Of course, you can generate your own profile, too, but the numbers will be a little different.