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From Thibaut Britz <thibaut.br...@trendiction.com>
Subject Re: Cluster load balancing?
Date Wed, 27 Oct 2010 18:27:28 GMT
Hello Tyler,

thanksf or the quick answer. That's true, I should have noticed.

I also tried kicking out one node, clearing all directories and then
restarting it with the bootstrap option. It received a few files, but just
set there in bootstrapping mode (streams always printed bootstrapping
without any files open), forever (> 15 minutes). I stopped the applicaiton
so it couldn't be load related, and also tried with a fresh cluster restart.
What could cause this?

(This should ahve the advantage of cassandra choosing a key in my range
which splits the range evenly?)


Thanks,
Thibaut







On Wed, Oct 27, 2010 at 7:40 PM, Tyler Hobbs <tyler@riptano.com> wrote:

> With OrderPreservingPartitioner, you have to keep the ring balanced
> manually.
> This is why people frequently suggest that you use RandomPartitioner unless
> you absolutely have to do otherwise.  With OPP, keys are *not* evenly
> distributed
> around the ring.
>
> Apparently you have lots of keys that are between ~'t' and 'x', so start
> bunching
> your tokens there.
>
> - Tyler
>
>
> On Wed, Oct 27, 2010 at 12:00 PM, Thibaut Britz <
> thibaut.britz@trendiction.com> wrote:
>
>> Hi,
>>
>> I have a little java hector test application running whcih writes and
>> reads data to my little cassandra cluster (7 nodes).
>>
>> The data doesn't get loadbalanced at all:
>>
>> 192.168.1.12 Up         178.32 MB
>> 8S6VvT7oKNcQTso3                           |<--|
>> 192.168.1.14 Up         30.12 MB
>> 9tybk3nB6JCtqQU1                           |   ^
>> 192.168.1.15 Up         11.96 MB
>> RZVG3NC3ksqjEmYE                           v   |
>> 192.168.1.16 Up         668.7 KB
>> aTV6W12YxxMI31Z8                           |   ^
>> 192.168.1.10 Up         22.86 GB
>> u5iaQxEfyUSwnPn1                           v   |
>> 192.168.1.13 Up         22.5 GB
>> vZlWeU8b6LBeAcAY                           |   ^
>> 192.168.1.11 Up         22.27 GB
>> xrmaUS6nnrYFSk8e                           |-->|
>>
>> What could be the issue? I couldn't find anything in the FAQ related to
>> this
>>
>> Will data (writes) always be added to the server I connect to? If so, why
>> will the replicas then always be stored on the same 2 other machines.
>>
>> (Tested with
>> <Partitioner>org.apache.cassandra.dht.OrderPreservingPartitioner</Partitioner>
>> on 0.6.5 and replication level 3)
>>
>> Thanks,
>> Thibaut
>>
>>
>>
>>
>

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