The ballot UUID is obtained using QUORUM agreement between replicas for a given partition key and we use this TimeUUID ballot as write-time for the mutation.
The only scenario where I can see a problem is that NTP goes backward in time on a QUORUM of replicas, which would break the contract of monotonicity. I don't know how likely this event is ... On Tue, Oct 10, 2017 at 9:07 AM, Daniel Woo <daniel.y....@gmail.com> wrote: > Hi guys, > > The ballot UUID should be monotonically increasing on each coordinator, > but the UUID in cassandra is version 1 (timestamp based), what happens if > the NTP service adjusts system clock while a two phase paxos prepare/commit > is in progress? > > -- > Thanks & Regards, > Daniel >
