Does Load Runner support JavaScript execution once response is received, unlike Jmeter? Because in JMeter when we received the response Page if it contains JavaScript or AJAX call then it is not process by JMeter? So is it supported by Load Runner or not?
Yes, TruClient Virtual User type, vesions 11.x and later.
Unless your code is truly asynchronous, where seperate threads are kicking off Javascript and the server requests are arriving substantially different in sequence every time, you really don't need JavaScript processing. Most of the AJAX clients out there are less 'A' and more 'S'ynchronous in their behavior when you look at the sequence of calls for a given business process across multiple recording sessions. Of the remainder that are truely 'A'synchronous in behavior, a substantial majority of the 'A' calls are to third party components that would not be included in your performance test anyway (Can you imagine trying to coordinate your performance test with people at Google because your app includes Google Maps!)
So, back your core core question. Yes, LoadRunner does include a Virtual User type which supports JavaScript processing, the TruClient Virtual User. You could also use a GUI Virtual User or a Citrix|RDP Virtual User if you wanted to run full browsers. To your larger question, do you really need a virtual user which processes JavaScript? Look carefully at your request sequences across multiple recording sessions to understand whethere your business process is truly asynchronous in nature (with your servers and your code) or is synchronous in behavior with your application.