Performance of Array vs. Object (v201)

Revision 201 of this benchmark created by Donato on

Description

After seeing http://jsperf.com/javascript-associative-vs-non-associative-arrays, I thought the test could be improved.

Setup

var arr = [],
        i,
        obj = {},
        array = new Uint8Array(10000);
    for(i = 0; i < 10000; i += 1) {
        arr.push(i);
        obj[i] = i;
        array[i] = i;
    }

Test runner

Ready to run.

Testing in
TestOps/sec
Array Performance
var sum = 0;
for (var x=0; x<arr.length; ++x) {
    sum += arr[x];
}
ready
Object Performance
var sum = 0;
for (var x in obj) {
    sum += obj[x];
}
ready
Object Performance using known length
var sum = 0;
for (var x=0; x<10000; ++x) {
    sum += obj[x];
}
ready
Using Object.keys()
var sum = 0;
var keys = Object.keys(obj);
for (var x=0; x<keys.length; ++x) {
    sum += obj[keys[x]];
}
ready

Revisions

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