timing-map.js

var n = 15000;

// Switching from repeat to map(fn, _.range(n)) causes this to use lots of
// memory. (~1GB)

// Setting n = 20000 gives "Allocation failed - process out of memory". Up the
// limit with e.g. node --max-old-space-size=2000

var data = repeat(n, function(i) {
  var obj = {
    name: uniformDraw(['foo', 'bar', 'baz']),
    value: randomInteger(100)
  }
  // if (i % 500 === 0) {
  //   display(process.memoryUsage().rss / Math.pow(1024, 3));
  // }
  return obj
});

map(function(i) {
  var d = data.slice(0, i * 1000);
  var start = Date.now();
  map(function(obj) { return d.name === 'foo'; }, d);
  var end = Date.now();
  //console.timeEnd('filter ' + i + 'k');
  //display((process.memoryUsage().rss / Math.pow(1024, 3)) + ' GB');

  console.log([i + 'k',
               end - start,
               process.memoryUsage().rss / Math.pow(1024, 3)].join(','))
  //return
}, _.range(n / 1000))