DOM creation & update benchmark

benchmark.js

(function () {
    // Creation V1
    console.time('v1');
    var s = document.createElement('select'),
        i, html = '';
    s.multiple = true;
    for (i = 0; i < 5000; i++) {
        html += '<option selected value="' + i + '">id #' + i + '</option>';
    }
    s.innerHTML = html;
    document.body.appendChild(s);
    console.timeEnd('v1');

    // Update
    console.time('update');
    Array.prototype.forEach.call(s.querySelectorAll('option'), function (opt) {
        opt.selected = false;
    });
    console.timeEnd('update');
})();

(function () {
    // Creation V2
    console.time('v2');
    var s = document.createElement('select'),
        i, opt;
    s.multiple = true;
    document.body.appendChild(s);
    for (i = 0; i < 5000; i++) {
        opt = document.createElement('option');
        opt.selected = true;
        opt.value = i;
        opt.innerHTML = 'id #' + i;
        s.appendChild(opt);
    }
    console.timeEnd('v2');
})();