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From Eric Stevens <migh...@gmail.com>
Subject Re: nodetool ring showing different 'Load' size
Date Mon, 17 Jun 2013 15:41:35 GMT
Load is the size of the storage on disk as I understand it.  This can
fluctuate during normal usage even if records are not being added or
removed, a node's load may be reduced during compaction for example.
 During compaction, especially if you use Size Tiered Compaction strategy
(the default), load may temporarily double for a column family.


On Mon, Jun 17, 2013 at 11:33 AM, Rodrigo Felix <
rodrigofelixdealmeida@gmail.com> wrote:

> Hi,
>
>    I've been running a benchmark on Cassandra and I'm facing a problem
> regarding to the size of the database.
>    I performed a load phase and then, when running nodetool ring, I got
> the following output:
>
> *ubuntu@domU-12-31-39-0E-11-F1:~/cassandra$ bin/nodetool ring *
> *Address         DC          Rack        Status State   Load
>  Effective-Ownership Token                                       *
> *
>                    85070591730234615865843651857942052864      *
> *10.192.18.3     datacenter1 rack1       Up     Normal  2.07 GB
> 50.00%              0                                           *
> *10.85.135.169   datacenter1 rack1       Up     Normal  2.09 GB
> 50.00%              85070591730234615865843651857942052864*
>
>    After that I executed, for about one hour, a workload with scan and
> insert queries. Then, after finishing the workload execution, I run again
> nodetool ring and got the following:
>
> *ubuntu@domU-12-31-39-0E-11-F1:~/cassandra$ bin/nodetool ring *
> *Address         DC          Rack        Status State   Load
>  Effective-Ownership Token                                       *
> *
>                    85070591730234615865843651857942052864      *
> *10.192.18.3     datacenter1 rack1       Up     Normal  1.07 GB
> 50.00%              0                                           *
> *10.85.135.169   datacenter1 rack1       Up     Normal  2.15 GB
> 50.00%              85070591730234615865843651857942052864*
>
>    Any idea why a node had its size reduced if no record was removed? No
> machine or added or removed during this workload.
>    Is this related to any kind of compression? If yes, is there a command
> to confirm that?
>    I also faced a problem where a node has its size increased from about
> 2gb to about 4gb. In this last scenario, I both added and removed nodes
> during the workload depending on the load (CPU).
>    Thanks in advance for any help.
>
>
> Att.
>
> *Rodrigo Felix de Almeida*
> LSBD - Universidade Federal do CearĂ¡
> Project Manager
> MBA, CSM, CSPO, SCJP
>

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