Load Testing Vaadin

Does anyone know if HP LoadRunner or NeoLoad is able to load/stress test Vaadin applications? I’ve not seen any other load testing related documentation except for Vaadin/JMeter.


I am very interested in a response to this. Perhaps someone from Vaadin could reply as to whether these tools should work to test a Vaadin application.


I am very interested in hearing about this too. Particularly, after hitting some major performance issues.

Julio V.


I tried the following scenario: Created a Vaadin portlet application (version 6.6.2) and deployed in Liferay (version 6.0.6 running on Tomcat)… this Vaadin app works OK as a portlet when accessed through browsers like IE (6, 7, 8), FF, Chrome, Safari… tried to use NeoLoad for load testing by accessing the same Liferay… the initial non-Vaadin login and other resources came through OK in the response… but the Vaadin portlet response as seen in the NeoLoad test result was “You have to enable javascript in your browser to use an application built with Vaadin”… is this some configuration I might have missed in NeoLoad?

Some guidelines on the following will help:

1> Should load testing of Vaadin apps work the same way irrespective of whether they are deployed as portlets or not? e.g. Will testing using JMeter (http://vaadin.com/wiki/-/wiki/Main/JMeter%20Testing?p_r_p_185834411_title=JMeter%20Testing) work for
Vaadin-based portlets
as well?

2> Is it possible in the first place to use tools like LoadRunner, NeoLoad, Grinder for load testing Vaadin apps? If yes, are there any examples available?



I’m bumping this subject because our company will use Vaadin in the future and I was asked to investigate load testing tools.
For our actual application which uses XML and blazeDS/AMF we wrote quite complex scripts with Jmeter.
Our scenarios are able to login, get a welcome page, pick a random item on that page, use it to trigger other random scenario where we pick other items…

With the way Vaadin works (client sessions on the server sending gui event via json to the browser) it is impossible to use Jmeter with such complex scenarios. I know some load testing were done with Vaadin and jmeter (ticket reservation), but the scenario used is really simple and basic.

There is also a grid for Selenium but I doubt it is able to simulate 100 or 200 concurrent users as easy as Jmeter. Moreover each client simulation might be high cpu demanding.

Are there some plans or roadmap regarding load testing tools for Vaadin?
Should we try to develop our own Jmeter components to simulate what the browser send?



We simulated 2000 concurrent users on EC2 with HTMLUnit for a scalability study. This required 10 XL servers and was hard to orchestrate. More information about the experiment here
. The HTMLUnit based tests were hand coded, but nowadays one could probably use Selenium 2 with HTMLUnit backend instead of hand-coded tests.

Later we dropped the HTMLUnit based simulation in favor of JMeter to be able to simulate 10x more users on the same servers. Using JMeter has its pitfalls, but in the end is much more scalable and easy to use. One particular pitfall is that one needs to be able to guarantee that ID:s for the UI components do not change during the test. For quick tickets study we got into problems with dynamic forms where new selections were created based on the previous selections. To solve the problem, we added - solely for testing purposes - a “i feel lucky with the next selection” button to form. This basically randomized the selections on the server side and still simulated the same load for the application. For details on this test - including sources and all scripts, see

To answer the question that Rowell asked earlier in the thread (and has been discussed since), the short answer is that yes, NeoLoad works very easily with Vaadin. The Vaadin framework is built on (among other things) Ajax and GWT technologies, things that are supported very well by NeoLoad. NeoLoad is also a much easier to use tool than the others listed here (LR, JMeter, etc) so not only will you find the support for Vaadin that is lacking in some other tools but you’ll also be able to get more work done in a shorter time.
For those interested, I would highly recommend taking a look at the free trial version of NeoLoad and/or checking out the
Neotys website for more information
Steve Weisfeldt Neotys Sr Performance Engineer

Hi All,

We are trying do load test of our vaadin application using jmeter. But while recording using jmeter record controller , it is not able to record tab clicking or button clicking event on vaadin portlets.

Any suggestion regarding this will be highly appreciated.

Chinmaya Sahu

Does anyone have an idea how I can do a load test of a vaadin web app with JMeter for multiple user login ? The general way to go is via a csv data set. When I inspect my post request in the vaadin web app containing the login credentials I don’t see a a separate username and login parameter field . So I am at a loss to understand how to use the csv file with my login post request.

Any suggesstions will be really helpful.

Thanks !