How to configure a load balancer on a local machine for testing/experimental purposes?

Hi,

In my local Apache, I have configured two virtual hosts one listening on port, say, 8081, and the other one on 8082. They both serve the same app.

I want to run a load balancer locally, say, on port 9090, that distributes the load between these two virtual hosts.

Could someone please explain how can I do this? Or point me to a tutorial/article describing how this can be done?

Thanks in advance.