[
https://issues.apache.org/jira/browse/CASSANDRA-5062?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13586297#comment-13586297
]
Jonathan Ellis commented on CASSANDRA-5062:
-------------------------------------------
I don't think leader-election CAS masters are quite that simple:
# Spinnaker requires ZK for state besides leader elections (section 4.1).
Leader elections alone are easy to do without full ZK; the rest of the
Spinnaker cluster state does not look so simple.
# Spinnaker-style (Kafka-style? I think they are basically the same)
replication requires a bunch of storage engine changes as well (section 4.2).
> Support CAS
> -----------
>
> Key: CASSANDRA-5062
> URL: https://issues.apache.org/jira/browse/CASSANDRA-5062
> Project: Cassandra
> Issue Type: New Feature
> Components: API, Core
> Reporter: Jonathan Ellis
> Fix For: 2.0
>
>
> "Strong" consistency is not enough to prevent race conditions. The classic
> example is user account creation: we want to ensure usernames are unique, so
> we only want to signal account creation success if nobody else has created
> the account yet. But naive read-then-write allows clients to race and both
> think they have a green light to create.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
