Compute jvm heap size to host web application

Question

I want to host a web application on a private JVM they offer 32, 64, 128, 256 MB plans.

My web application uses Spring. And I store some objects for every logged in user session.

My question is: How can I profile my web app to see how much heap size it needs so I can choose a plan?, How can I simulate hundreds of users logged in at the same time?

I'm developing the application using Netbeans 6.7 Java 1.6 Tomcat 6.0.18

Thank you.

Laevorotatory

Answer 1

• For profiling you can use VisualVM, YourKit, etc.
• For simulating load you can use Apache JMeter

Crisscross

But if I want to simulate load and see how does the memory increases with every new user do I need to use JMeter in conjunction with VisualVM or YourKit? – Laevorotatory

Jmeter can be used to create/simulate load and VisualVM or Yourkit can be used to profile the app under load, so yes. You'd want to use them together. – Crisscross

Answer 2

I'd recommend using a tool like JMeter to do your load testing. You can use jvisualvm to see basic heap usage or grab a heap dump to see exact details.

Linalinacre

Answer 3

jVisualVM is a great option to observe your application's usage of JVM memory.

However, once you're up and running, you might want to check the JVM's memory usage statistics from time to time without having to get to a console to run jVisualVM. If you do, this simple web application (heap visualizer) might be of help.

You could protect the application by modifying the web.xml so that only selected roles have access to this application.

Thornhill