[dragonwriter]

> Does adding timestamps not handle this case?

If you have one message source (a single thread or some kind of coordination), and the messages have lower frequency than the timestamp resolution, yes.

The farther you get from that, the more the answer is no.

[amelius]

Just make the source part of the timestamp?

(1,A) < (1,B) < (2,A) etc.

Also use serial numbers instead of true timestamps.

[rsynnott]

That way lies madness, and/or eventually accidentally writing your own Dynamo-paper database.