Remove older geoxml3 layers when refresh

Question

I have a google map on my web page, and uses geoxml3 to parse the layers (with many placemarks).

There is a timer that will trigger a jquery every 10 seconds to pull the new .kml file. However I want to remove the old layer, before parsing the new layer.

Question: What is the right way of removing/destroying?

I know there is a geoXml.hideDocument(); , but that only hides the layer, it does not remove/destroy the layer right? (below is the hideDocument() implementation)

refreshMap() - hide previous layer and show new layer

$.ajax({
    url: url,
    dataType: 'json',
    type: 'get',
    contentType: 'application/x-www-form-urlencoded',
    data: "",
    success: function (data, textStatus, jQxhr) {
        if (data['success'] == 1) {
            if (geoXml) 
                geoXml.hideDocument();
            var src = data['kml'];
            geoXml = new geoXML3.parser({
                map: map,
                suppressInfoWindows: false,
                singleInfoWindow: true,
                infoWindow: infowindow,
                zoom : false
            });
            geoXml.parse(src);
            geoXml.showDocument();
        }
    },
    error: function (jqXhr, textStatus, errorThrown) {
        console.log(errorThrown);
    }
});

Even though this works, but my worry is that if it keeps pulling data every 10 seconds, if the page is opened for 1 hour, will it cause any lag? Reason being that the overlays are not actually destroyed/removed, they are still on memory, just that we lose the reference to it (because now reference point to the new layer).

Update

I found some information online, seems like I don't have to worry about this implementation.

"Since Javascript is garbage collected, you don't need to delete objects themselves - they will be removed when there is no way to refer to them anymore."

Answer 1

I have a test case that effectively does this:

filename="http://www.geocodezip.com/dynamicmarkerkml.php";
geoXml.parse(filename);
setInterval("geoXml.hideDocument();geoXml.parse(filename)", 5000);

Doesn't leak memory that I can see and I have had it running for days (at one point, not recently).