What is Appstats? https://developers.google.com/appengine/docs/python/tools/appstats https://developers.google.com/appengine/docs/java/tools/appstats A tool to help you make your application fast Appstats helps you: see where you're waiting for network calls figure out how to make RPC calls efficiently track RPC costs notice where you should be caching data rather than making repeated RPC calls Wi