How to Fix Poor Performance on Filter By Text - performance

Question

A while back I found some code that allows you to filter the contents of a SELECT by typing in a text element. It works well however, over time the performance degrades pretty badly. I'm not sure if it is the filter code or the way in which I am activating it.
The SELECT shows up in a modal dialog (bootstrap) so I have the following code:
$('#myModal').on('shown', function () {
$(".focusable").val("").focus();
var select = $('#myModal').find(".modal-body").find("select");
var text = $('#myModal').find(".modal-body").find("input[type='text']");
select.filterByText(text, true);
});
And here is the filter code:
jQuery.fn.filterByText = function (textbox, selectSingleMatch) {
return this.each(function () {
var select = this;
var options = [];
$(select).find('option').each(function () {
options.push({value:$(this).val(), text:$(this).text(), data:$(this).data("short-name")});
});
$(select).data('options', options);
$(textbox).bind('change keyup', function () {
var options = $(select).empty().data('options');
var search = $.trim($(this).val());
var regex = new RegExp(search, 'gi');
$.each(options, function (i) {
var option = options[i];
if (option.text.match(regex) !== null) {
var copyOption = $('<option>').text(option.text).val(option.value);
copyOption.data("short-name", option.data);
$(select).append(copyOption);
}
});
if (selectSingleMatch === true &&
$(select).children().length === 1) {
$(select).children().get(0).selected = true;
}
});
});
};
Can anyone shed some light on where my performance issue(s) might be and how to solve it?

Answer 1

reading through the comments I would suggest to add the following:
$(textbox).bind('change keyup', function(event) {
console.log(event);
// your code
});
Is the event triggered more than once on a single keyup after some times the dialog is shown?
$('#myModal').on('hidden', function () {
$('#myModal').find(".modal-body").find("input[type='text']").off("change keyup");
});