Performance degradation with JSF, Spring, Hibernate application

Question

I'm working on web application developed by the following technologies (JSF, Spring, Hibernate, MySQL, MongoDB, Elasticsearch, Jetty server and Tomcat). I created a stress test that simulates the application use by one user. In test scenario, I'm running a stress test for 4 paralel users, and in the same time login as 5th user and measure system response time for certain activities. If we present a response time when stress time is not running as T, after 5 minutes of running stress test response time is ~2xT, after 30 minutes it's ~5xT, after 45 minutes it's ~10-15xT.

After 1 hour I stopped the tests, waited 25 minutes untill memory heap was less then 200mb and CPU use near 0%, and performance got better slightly, but not too much (~7T). 1 hour after the tests stopped nothing changed.

My PC has 8GB of RAM, and I run the application with -Xms512m -Xmx4092m -XX:PermSize=512m -XX:MaxPermSize=512m, and according to what I found from JVisualVM and JProfiler, I don't think this is a memory leak issue. However, I'm not sure what else could be the problem. I hope someone could indicate what should be a possible reason for such a huge performance degradation or where should I look for it.

Thanks in advance.

Answer 1

After having analysed all aspects of the application I identified that Mojarra was the main reason for performance degradation. Ajax post response time has been longer while backend initialization remained the same after a stress tests. After moving from Mojarra 2.1.9 to 2.2.0, problems disappeared, and I believe that is related to the complexity of JSF pages and how Mojarra deals with big number of components on one page.