Quorum reads and writes in Cassandra guarantee sequential consistency. The reason this doesn't satisfy linearizability is because resurrections of unacknowledged writes can occur. A read of a half-committed write will trigger synchronous read repair and the order will be stable from that point forward.
Isolation is an unrelated issue. Evan On Wed, Oct 15, 2014 at 4:45 PM, Timmy Turner <timm.t...@gmail.com> wrote: > Cassandra in general can't provide guarantee any ordering of the executed > queries, since nodes may fail or rejoin the in arbitrary points in time. > > But why can't it provide ordering for queries run at at least the quorum > level? Given that none of the updates get lost, why would order still an > issue? > > Can you maybe illustrate a scenario which shows how/where the order would > get lost if writes and reads always occurred with quorum consistency?
