Code review comment for lp:~stub/launchpad/update-storm

Bug #393625 was raised because one of our scripts was using an unacceptable amount of RAM. Testing showed reducing the Storm cache size fixed the problem. Most likely, this script is dealing with objects containing long text columns.

This branch changes the default Storm cache size to be much more conservative. It also adds a load of boilerplate so we can easily override the conservative default for individual components where we detect slowness due to cache thrashing and can afford to use more RAM.

The appserver cache size settings remain unchanged from the value we have been running on edge for the last few weeks.

I would like to get this branch landed release critical so we don't have to cherry pick or disable update-pkgcache.