Wouldn't a partial order be possible using logical clocks? Vector clocks probably don't satisfy "practical" but a hybrid logical clock is practical if you can assume clock synchronisation is within some modest delta.
> The Lamport timestamp algorithm is a simple logical clock algorithm used to determine the order of events in a distributed computer system. As different nodes or processes will typically not be perfectly synchronized, this algorithm is used to provide a partial ordering of events with minimal overhead, and conceptually provide a starting point for the more advanced vector clock method.
