Array Performance

JavaScript performance comparison

Revision 9 of this test case created


Manual array lookups vs. holey arrays.

Preparation code

  Benchmark.prototype.setup = function() {
    var a1 = [{id: 29938, name: 'name1'}, {id: 32994, name: 'name1'}];

    var a2 = [];
    a2[29938] = {id: 29938, name: 'name1'};
    a2[32994] = {id: 32994, name: 'name1'};

    var a3 = [];
    a3['29938'] = {id: 29938, name: 'name1'};
    a3['32994'] = {id: 32994, name: 'name1'};

    var o = {};
    o['29938'] = {id: 29938, name: 'name1'};
    o['32994'] = {id: 32994, name: 'name1'};

Test runner

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Testing in unknown unknown
Test Ops/sec
Holey Array by String Index
var id = '29938';
var result = a3[id];

Holey Array by Index
var id = 29938;
var result = a2[id];
Object by Key
var id = '29938';
var result = o[id];

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