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On Tue, 2014-09-02 at 17:34 +0300, Dmitriy Ukhlov wrote:
> Hi Romain!
> 
> 
> Thank you for useful info about your Cassandra backuping.

It's always a pleasure to talk about Cassandra :)

> 
> We have not tried to tune Cassandra compaction properties yet.
> 
> MagnetoDB is DynamoDB-like REST API and it means that it is key-value
> storage itself and it should be able to work for different kind of
> load, because it depends on user application which use MagnetoDB.

The compaction strategy choice really matters when setting up a cluster.
In such a use case, I mean MagnetoDB, we can assume that the database
will be updated frequently. Thus LCS is more suitable than STCS.


> Do you have some recommendation or comments based on information about
> read/write ratio?

Yes, if read/write ratio >= 2 then LCS is a must have.
Just be aware that LCS is more IO intensive during compaction than STCS,
but it's for a good cause.

You'll find information here:
http://www.datastax.com/dev/blog/when-to-use-leveled-compaction

Best,

Romain