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From Robert Coli <rc...@eventbrite.com>
Subject Re: not even number of keys per CFs in fully balanced cluster with random partitioner
Date Tue, 29 Oct 2013 23:41:25 GMT
On Tue, Oct 29, 2013 at 4:39 PM, Robert Coli <rcoli@eventbrite.com> wrote:

> On Tue, Oct 29, 2013 at 4:09 PM, Piavlo <lolitushka@gmail.com> wrote:
>
>> I can't understand how statistically it's possible that with random
>> partitioner some nodes have x2 more keys than others with 50-100 millions
>> of keys per node.
>>
>
> 1) you have very high row variance and really really bad luck with the
> distribution of your super-huge rows
>

Oh, herp, you specified that you have a number-of-keys difference. So it
can't be this one.

But..

First, that number of keys is the number of keys *SEEN BY COMPACTION SINCE
NODE STARTUP* so different runtimes can skew numbers.

Second, that number of keys is the number of times the key has been seen in
all sstables. A single row key with fragments in 5 sstables = "5".

Have you added nodes to the cluster and not run a cleanup compaction?

=Rob

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