Improve instance startup

[yissachar]

Current startup time:

Test site (F1 instance): 17 seconds Production site (F2 instance) 15 seconds

To some extent this is out of our control due to https://code.google.com/p/googleappengine/issues/detail?id=7706, however there are a few things we can investigate which may be able to speed things up:

• [ ] Use Dagger instead of Guice for Dependency Injection
• [ ] Run Proguard on WAR before deploying to AppEngine
• [ ] Replace Jersey with alternative REST framework that doesn't require classpath scanning (maybe http://www.sparkjava.com/)

[yissachar]

The above times were pulled from a single measurement. Pulling the last 10 startup times from AppEngine logs gives us the following results instead:

Test site: 13.7 seconds Production site: 10.9 seconds

[yissachar]

Removing lots of unused static content (2625e0a49188c24cf4a3f0a3bb3d04039ce6decc) seems to have marginally improved startup time:

Test site: 12.7 seconds

[yissachar]

Testing with server startup code omitted gives startup times of ~5s.

[yissachar]

enableJarClasses maven setting does not seem to affect startup time.

[yissachar]

Removing all handlers from web.xml besides for welcome file list and guice listener brings time down to 4s.