measure time spent on a web page [duplicate]

Question

Possible Duplicate:
How to measure a time spent on a page?

I am trying to get the time spent on some of the pages in my site. One way I am thinking to implement is polling the server with ajax request every 10 sec , but this would mean a lot of request for the server.

Is there any better way to implement the feature ?

Thanks.

Answer 1

Could you not just use a single AJAX request to inform the server of the page unload event?