As you know, browser can store some downloaded HTML/JPG/etc file from remote server on local hard drive so you can access it faster next time. This is called “cache”.

There is an option in LoadRunner VuGen to simulate browser cache behavior with your web performance testing. But how to use it and when? Here are my suggestions.

Don’t clean the cache
Your application is rather something internal used by (mostly) the same people in one company – In that case I suggest not to clean the cache because this will reflect users behavior in your tests. If you ask why? then ask yourself how often you clean your browser cache. Once a week? Once a month? Every login/logout? Are you getting the idea?

With such settings, your transaction performance graph would look like this:

After first iteration with cache enabled, transaction performance is much smaller. It’s because user gets most of the files from the cache.

Clean the cache:
Your application is accessible from the Internet, and your customers are basically everyones on the net – in that case I suggest to clean the cache because its more probable to have new person without cached content already.

This is example performance graph after tests with cleaning browser cache.

In each iteration, user has empty cache at the beginning so he need to get all the files from remote server.

Conclusion:

Only by cleaning/not cleaning the cache your transaction performance can vary significantly!!!