Array Performance

JavaScript performance comparison

Revision 37 of this test case created


Manual array lookups vs. holey arrays.

Preparation code

  Benchmark.prototype.setup = function() {
    var a1 = [], o = {}, a2=null;
    for( var i=0; i <=5000; i ++){
      a1.push( { id: i, name: 'name' });
      o[i] = { id: i, name: 'name' };

Test runner

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Testing in unknown unknown
Test Ops/sec
Manual Array Lookup
var id = 500;
for (var i = 0; i < a1.length; i++) {
  if (a1[i].id == id) result = a1[i];
Object by Key
var id = 500;
var result = o[id];

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