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From Jeremy Hanna <jeremy.hanna1...@gmail.com>
Subject Re: 4/20 nodes get disproportionate amount of mutations
Date Mon, 29 Aug 2011 02:38:20 GMT
I just mean that when it tries to put a replica on another "rack" which is part of what the
replication strategy does in case a whole rack goes down, it looks to the next token in the
ring that is on another rack.  If you don't alternate racks (or in this case availability
zones) in token order, that can lead to serious hotspots.  For more on this with ec2, see:
http://www.slideshare.net/mattdennis/cassandra-on-ec2/5 where he talks about alternating zones.

On Aug 25, 2011, at 10:45 AM, mcasandra wrote:

> Thanks for the update
> 
> Jeremy Hanna wrote:
>> 
>> It appears though that when choosing the non-local replicas, it looks for
>> the next token in the ring of the same rack and the next token of a
>> different rack (depending on which it is looking for).  
> 
> Can you please explain this little more?
> 
> 
> --
> View this message in context: http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/4-20-nodes-get-disproportionate-amount-of-mutations-tp6714958p6724943.html
> Sent from the cassandra-user@incubator.apache.org mailing list archive at Nabble.com.


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