How to add markers bulk in leaflet?

Question

I have an array with ~30k elements and I need to create map with markers for each of them. I use markerclusters and trying to optimize adding moment.

for (var i = 0; i < myItems.length; i++) {
    var item = myItems[i];

    marker = new L.marker([item[2],item[3]], {
        icon: mapOpts.myIcon
    }).bindPopup(item[1]);

    markers.addLayer(marker);

}

Even Google Chrome takes about 40 sec to do this loop. I don't want to see FF's result.

Is there any way to optimize adding many elements to map?

Answer 1

var markerArray = [];
markerArray.push(L.marker([51.505, -0.09]));
...
var group = L.featureGroup(markerArray).addTo(map);
map.fitBounds(group.getBounds());

Answer 2

var array = [];

for (var i = 0; i < myItems.length; i++) {
    var item = myItems[i];

    marker = new L.marker([item[2],item[3]], {
        icon: mapOpts.myIcon
    }).bindPopup(item[1]);

    array.push(marker);
}

markers.addLayers(array);

See the docs for more details.