@nodejs and object sort speed

I was coding a scheduler and needed a sorted array of the schedules, so I started to investigate the speed of different sorting variants I could use.

I created a little program (https://gist.github.com/flogvit/c9df93ab37ca4dbd2d7f) to test 4 different variants.

For the test I created an array with 100000 objects { v: num }, where num is 100000 to 1. v is the value I want to sort on. Then I did the sort 10 times for each variant, and then again running this 5 times.

The first variant was standard compare (compare):

function compare(a, b) {
  if (a.v < b.v)
    return -1;
  if (a.v > b.v)
    return 1;
  return 0;
}

sortarray.sort(compare);

The second was a value only version doing the minus variant (compareValue):

function compareValue(a, b) {
  return a.v - b.v;
}

sortarray.sort(compareValue);

Third variant is using async (async):

   async.sortBy(sortarray, function (entry, callback) {
      callback(null, entry.v);
    }, function (err, results) {
      sortarray = results;
    });

And last variant is using underscore (underscore):

sortarray = _.sortBy(sortarray, 'v');

The result where smaller is better:

compare 36.00
compareValue 36.58
underscore 50.84
async 228.48

And the full output from each run:

$ node --expose-gc sort.js
Running compare for average 30.8 ms
Running compareValue for average 38 ms
Running async for average 227 ms
Running underscore for average 51.8 ms
Running compare for average 38.8 ms
Running compareValue for average 36.6 ms
Running async for average 230.7 ms
Running underscore for average 49.5 ms
Running compare for average 37.2 ms
Running compareValue for average 35.2 ms
Running async for average 234.7 ms
Running underscore for average 52.6 ms
Running compare for average 37.4 ms
Running compareValue for average 37.1 ms
Running async for average 224.4 ms
Running underscore for average 49.4 ms
Running compare for average 35.8 ms
Running compareValue for average 36 ms
Running async for average 225.6 ms
Running underscore for average 50.9 ms