Question

Are there best practises how to improve the performance of spring webapps?

I use ehcache for static content, try to load JavaScript at the end of my app but the app doesn’t run smooth yet. For a simple registration only the GET-request to map the url and initalize session and bean lastet over 7 sec.

Sure you can optimize a lot for specific, but I’d like to know about generell performance issues and how to handle those.

Patterns, best practises and so on are very wellcome here.

Answer 1

In general, I recommend:

• build a test environment where you can execute the application and
  get at the inside
• Write repeatable performance testing scripts, focusing both on absolute performance (e.g. “how long does it take to render this page”) and performance at scale (e.g. “how does performance degrade under load?”)
• glue a profiler into your test environment. It’s been a while since I worked on Java apps, but there are lots of them available.
• run performance test whilst running your profiler. Work out what the bottleneck is. Fix the bottleneck. Rinse. Repeat.

I generally recommend NOT to have the test rig be similarly specified to production, because it makes it very hard to create enough load to stress the system. It’s also very expensive.

If you have a “production-like” environment to test on, do it now – ideally, you’ll get similar results as on the test environment, but not always; if at all possible, install the profiler and see where the bottleneck is.

Once you’ve done that, you can deploy the optimized app to your production environment.