Enterprise Application Performance Fine tuning is very important.
Measure the performance at different layers.
Step 1: Prevention (Design, Code Reviews, Alerts, Dashboards, Caching techniques)
Step 2: Detection (Performance testing, Set Alerts and Dashboards, Log and Monitor apps, Service Attacks)
Step 3: Recovery in Production (Restrict Traffic, Allocate more resources like space, memory, cpu…until we fix the issue., Restart)
Different levels of performance fine tuning.
1. JVM Fine tuning
2. OS (JVM Running) fine tuning
3. Database Fine Tuning
4. Application Fine Tuning
5. UI Fine Tuning: http://polimetla.com/2012/10/19/web-page-testing-tools/
6. Network Fine tuning. (http://bluestripe.com/)
Each step is big subject and contact me for more help.
Visual VM: http://visualvm.java.net/