Rewrite (incrementally or in full) the ContributionTracking modules. This work is complete when we no longer have a SPOF in contribution tracking data.
- Ideally we consolidate to a single PHP library.
- Schema migration must be deployed ever so carefully, and with no irreversible steps until we're 100% confident in the new data. This is everything we own, don't set it alight.
- Push on timeline for Redis 3 clustering support, which allows for invisible high availability with no added code complexity. See Redis 2 HA hooks in DI::DonationQueue to see why this is important.
- Shared sequence generator.
- Entries older than 1 hour can be kept in cold storage.
- We'll need a staging Redis cluster for QA.
- Vagrant module to easily provision a 2+ -node Redis cluster.