DynamicSettings should be rewritten to use Redis for wgConf, so we can store the whole of the json file in Redis instead of reading it from the cache. It is likely faster, but we'll need to benchmark it, and it saves messing about with trying to sync both cache files up on all of the servers.

The Redis server would need to be persistent for this, and we can potentially bring the data into PHP's cache too to ensure that it is quicker given that Redis is on a different server.