Performance Cost of Profiling a Web-Application in Production

Question

I am attempting to solve performance issues with a large and complex tomcat java web application. The biggest issue at the moment is that, from time to time, the memory usage sp

Answer 1

There is nothing wrong in profiling production apps. If you work on distributed applications, there are times when a outofmemory exception occurs in a very unique probability scenario which is very difficult to reproduce in a dev/stage/uat environment.

You can try using custom profilers but if you are in a hurry and plugging in/ setting upa profiler on a production box will take time, you can also use the jvm to take a memory dump(jvms memory dump also gives you thread dump)

1. You can activate the automatic generation on the JVM command line, by using the following option : -XX:+HeapDumpOnOutOfMemoryError

2. he Eclipse Memory Analyzer project has a very powerful feature called “group by value”, which makes it possible to build an object query and regroup the instances by a field value. This is useful in the case where you have a lot of instances that are containing a smaller set of possible values, and you can to see which values are being used the most. This has really helped me understand some complex memory dumps so I recommend you try it out.