[snuxoll]

I suppose at Facebook scale it might be infeasible, but couldn't you get the same effect by archiving log segments and a periodic binary full backup? This is precisely what I do with my PostgreSQL databases (though with some friendly automation with pg barman), I assume you could do the same with some tooling around MySQL's binlog facilities.

[evanelias]

Yes, although if using the binlogs as-is, that's effectively incremental backup instead of differential. The disadvantages of incremental solutions are that they require more storage and take longer to restore (especially if only doing full backups every few days); the upside is less complexity.