I need to make performance test of Mule ESB. I have an access to 10+ amazon machines. I must create my own application for loading this machines or use existent application. Can you give me any ideas for loading Mule ESB from my application or what application i need to use?
You need to use or create a test application that is representative of the actual application that will be deployed on EC2.
The reason is that you can combine Mule's building blocks (transports, in and outbound endpoints, transformers...) in an infinite number of combinations and the behavior of the application under load will vary greatly across these combinations.
So better build a small Mule application that represents the most critical slice of functionality you'll have in the actual application and load test it.
Also be careful with one thing: Mule applications are oriented towards integration so they interact with external systems a lot. You may not want to indirectly load test an third party application by load testing your Mule application. Better dedicate a few of your 10 machines to run stubs of the remote applications Mule will interact with (that will also let you test things like: what if the remote app is slow? or down?).