Why Load Testing Ajax is Hard

ajaxian.com

3 pointsrickharrison2 comments

I don't see how you can scale the solution. To actually load test you'd need thousands of browser instances, which is not practical.

For example auto-complete has a built in delay of about half a second for each keystroke. So how do you load test that? The fastest you can go is two requests per second if you use a real browser.

Or hundreds of thousands of browser instances. The whole point of most load test tools is they can generate far more load per hardware unit (CPU, RAM, etc...) than browsers could due to being lighter-weight specialized programs.

I'm not sure why this is such an issue. Most commercial testing tools use proxy recorders which will happily record all the AJAX requests along with the normal requests, and will spit out test scripts that include the AJAX calls. If you don't want them all using "banana" then just record 10 different scripts (which you should be doing anyhow to cover the most common usage models/flows for your site).

Reply on news.ycombinator.com