Datatable: when using 3000 records my datatable is getting loading slowly, and when click on buttton on change action not responding immediately - datatables

Question

When I click on search button, my page getting freeze, alerts & masking are not working but when page loads completing alerts are popup.
Pleas help me on this
I have 3000 rows in a Datatable:
I Have two radio buttons
Show only Difference
All
When I click any one of button applyFitler function will get execute and executeFilter is filter function that executes when table is getting Draw,
What I expected is, when I click on any of Radio button, Mask with Please wait should show immediately, but it shows before one second (9th second) of returning results to Datatable. Total its taking 10 seconds to apply filter and return Datatable.
During these 10 seconds by browser page getting freeze
var applyFitler = function() {
alertBlock('Please wait..');
// clear the global search box
__DATATABLE.search('');
// set columnIndex to match data attribute of each column (used in our custom search while allowing moving of columns)
$('#devresult th').each(function(index) {
var headerText = $(this).data('col-header');
__TABLEHEADERS[headerText].columnIndex = $(this).data('column-index');
});
if (__DATATABLE != undefined) {
__DATATABLE.draw();
}
alertUnblock();
};
var executeFilter = function(settings, data, dataIndex, rowData, counter) {
var rows = __DATATABLE.rows({ 'search': 'applied' }).nodes();
var showRow= $("input[name=showRow]:checked").val();
if(showRow == "notshow") {
return false;
}
}
return true;
}