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From Evan Weaver <>
Subject Re: Why is Quorum not sufficient for Linearization?
Date Thu, 16 Oct 2014 17:16:59 GMT
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.


On Wed, Oct 15, 2014 at 4:45 PM, Timmy Turner <> 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?

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