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From Jonathan Ellis <jbel...@gmail.com>
Subject Re: New Features - Future releases
Date Sat, 19 Sep 2009 02:55:04 GMT
On Fri, Sep 18, 2009 at 9:09 PM, Jonathan Mischo <jmischo@quagility.com> wrote:
>>>        • 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.

Yes; that's what it's supposed to do, and it's satisfying a very real
use case: "I want my data's primary data center to be DC A, but I want
one replica in DC B in case A is completely unavailable."

Other use cases can use different Strategies.  That's why they're
pluggable.  It's not one-size-fits-all and it's not supposed to be.

-Jonathan

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