incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
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 23:39:22 GMT
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
OR
2) you have repaired some nodes and not others, and have dramatically
over-repaired the repaired ones, possibly due to f/e TTL + repair issues in
1.0.x

The simple way to see if #2 is the case is to run a major compaction on a
good and a bad node. They should end up the same size.

There are operational implications to doing a major compaction, however, so
you might want to investigate the use of checksstablegarbage [1].

=Rob
 [1] https://github.com/cloudian/support-tools

Mime
View raw message