How to track & trend end to end performance (the client experience)

I think you have good goals, but I would split them:

• Measuring DOM rendering, javascript rendering etc. are not really part of "experience from the client visiting this app via a browser", because your clients are usually unaware that you are "rendering dom" or "running javasript" - and they don't care. But they are something I'd want to address after every committed change, not just release to release, because it could be hard to trace degradation back to particular change if such test is not running all the time. So I would put it in continuous integration on build level. See a good discussion here

• Then you probably would want to know if server side performance is the same or worsened (or is better). For that JMeter is ideal. Such testing could be done on some schedule (e.g. nightly or on each release) and can be automated using for example JMeter plug-in for Jenkins. If server side performance got worse, you don't really need end-to-end testing, since you already know what will happen.

• But if server is doing well, then "end user experience" test using a real browser has a real value, so Selenium actually fits well to do this, and since it can be integrated with any of the testing frameworks (junit, nunit, etc), it also fits into automated process, and can generate some report, including duration (JUnit for instance has a TestWatcher which allows you to add consistent duration measurement to every test).

• After all this automation, I would also do a "real end user experience" test, while JMeter performance test is running at the same time against the same server: get a real person to experience the app while it's under load. Because people, unlike automation, are unpredictable, which is good for finding bugs.

1. Regarding "JMeter is not a browser". It is really not a browser, but it may act like a browser given proper configuration, so make sure you:

   • add HTTP Cookie Manager to your Test Plan to represent browser cookies and deal with cookie-based authentication
   • add HTTP Header Manager to send the appropriate headers

   • configure HTTP Request samplers via HTTP Request Defaults to

     • Retrieve all embedded resources
     • Use thread pool of around 5 concurrent threads to do it
   • Add HTTP Cache Manager to represent browser cache (i.e. embedded resources retrieved only once per virtual user per iteration)
   • if your application is build on AJAX - you need to mimic AJAX requests with JMeter as well

   Regarding "rendering", for example you detect that your application renders slowly on a certain browser and there is nothing you can do by tuning the application. What's next? You will be developing a patch or raising an issue to browser developers? I would recommend focus on areas you can control, and rendering DOM by a browser is not something you can.

2. If you still need these client-side metrics for any reason you can consider using WebDriver Sampler along with main JMeter load test so real browser metrics can also be added to the final report. You can even use Navigation API to collect the exact timings and add them to the load test report

   

   See Using Selenium with JMeter's WebDriver Sampler to get started.

3. There are multiple options for tracking your application performance between builds (and JMeter tests executions), i.e.

   • JChav - JMeter Chart History And Visualisation - a standalone tool
   • Jenkins Performance Plugin - a Continuous Integration solution