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From Tupshin Harper <tups...@tupshin.com>
Subject Re: Why is my cluster imbalanced ?
Date Mon, 07 Apr 2014 13:52:46 GMT
I recommend rf=3 for most situations, and it would certainly be appropriate
here.

Just remember to add a third rack, and maintain the able number of nodes in
each rack.

-Tupshin
On Apr 7, 2014 9:49 AM, "Oleg Dulin" <oleg.dulin@gmail.com> wrote:

> Tupshin:
>
> For EC2, 3 us-east, would you recommend RF=3 ? That would make sense,
> wouldn't it...
>
> That's what I'll do for production.
>
> Oleg
>
> On 2014-04-07 12:23:51 +0000, Tupshin Harper said:
>
>  Your us-east datacenter, has RF=2, and 2 racks, which is the right way
>> to do it (I would rarely recommend using a different number of racks
>> than your RF). But by having three nodes on one rack (1b) and only one
>> on the other(1a), you are telling Cassandra to distribute the data so
>> that no two copies of the same partition exist on the same rack.
>>
>> So with rack ownership of 100% and 100% respectively, there is no even
>> way to distribute your data among those four nodes.
>>
>> tl;dr Switch node 2 to rack 1a.
>>
>> -Tupshin
>>
>>
>>
>> On Mon, Apr 7, 2014 at 8:08 AM, Oleg Dulin <oleg.dulin@gmail.com> wrote:
>>
>>> I added two more nodes on Friday, and moved tokens around.
>>>
>>> For four nodes, the tokesn should be:
>>>
>>> Node #1:                                        0
>>> Node #2:   42535295865117307932921825928971026432
>>> Node #3:   85070591730234615865843651857942052864
>>> Node #4:  127605887595351923798765477786913079296
>>>
>>> And yet my ring status shows this (for a specific keyspace). RF=2.
>>>
>>> Datacenter: us-east
>>> ==========
>>> Replicas: 2
>>>
>>> Address        Rack        Status State   Load            Owns
>>> Token
>>>
>>> 42535295865117307932921825928971026432
>>> x.x.x.1  1b          Up     Normal  13.51 GB        25.00%
>>> 127605887595351923798765477786913079296
>>> x.x.x.2  1b          Up     Normal  4.46 GB         25.00%
>>> 85070591730234615865843651857942052164
>>> x.x.x.3  1a          Up     Normal  62.58 GB        100.00%             0
>>> x.x.x.4  1b          Up     Normal  66.71 GB        50.00%
>>> 42535295865117307932921825928971026432
>>>
>>> Datacenter: us-west
>>> ==========
>>> Replicas: 1
>>>
>>> Address        Rack        Status State   Load            Owns
>>> Token
>>>
>>> x.x.x.5   1b          Up     Normal  62.72 GB        100.00%
>>> 100
>>> --
>>> Regards,
>>> Oleg Dulin
>>> http://www.olegdulin.com
>>>
>>
>
> --
> Regards,
> Oleg Dulin
> http://www.olegdulin.com
>
>
>

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