we do async replication with good monitoring of the slaves to make sure the slaves don't get too far behind. couple that with wal-e. of course, if a comet hits

we do async replication with good monitoring of the slaves to make sure the slaves don't get too far behind. couple that with wal-e. of course, if a comet hits the master db server, you might lose a tiny bit data (typically 0.1 seconds) if not using sync replication. you can use sync replication for the important things that you absolutely can't lose, and async replication for everything else.