Recap

Approach #4: temporarily commit to another server's RAM for speed, eventually to disk
- some form of logging in RAM and batching writes to disk + checkpointing
- need to "shard" data for each server so that many server serve as a backup for a single master to speed recovery time
  - likely, backup shards will need to be able to temporarily become masters for the data while rebuilding the master

Backup and Recovery Revisited