On Sep 18, 2009, at 8:41 PM, Joe Stump wrote:


On Sep 18, 2009, at 9:33 PM, <cont...@shahan.me> wrote:

        • ACL

I'm strongly against ACL. Cassandra was built for highly scalable and highly distributed environments, which always sit behind firewalls. ALC's can easily be implemented in a service layer in front of Cassandra.

ACLs could also be implemented as a pluggable model that defaults to off, if you really needed a per-CF or per-keyspace ACL. Honestly, for what Cassandra does best, I think it'd have to be as lightweight as possible.

• Multiple data center replication in the background. maybe a multi master type thing

It already has this. It was built from the ground up for this. It's highly tolerant to partitioning and has always available writes. All replication is done in the background (unless you specifically set a write to a high consistency level).


You know, it does and it doesn't. RackAwareStrategy isn't a true N+1 scaling solution. Currently, RackAwareStrategy only guarantees that it will try to replicate data to one other data center and/or one other rack, depending on the number of replicas specified. It's just a problem with the logic used, if the partitioner has already found a node in another data center, it stops caring about whether additional replicas go to another data center, the same applies to racks...if it's already found a node in another racks, it stops trying to ensure additional replicas go to different racks. I'd go into more detail on this, but it gets into code, so it's really more appropriate for the dev list, or you can open a JIRA ticket and I'll comment on it in more detail.

This is something I'm considering working on, after I finish my work on mapped and classless EndPoint snitches.

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