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https://issues.apache.org/jira/browse/CASSANDRA-8460?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16414766#comment-16414766
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Ben Slater commented on CASSANDRA-8460:
---------------------------------------

I'm not sure it's necessarily easier (because you now have two separate pools 
of disk to manage) but I think it is more predictable - your data will be 
always be on the fast disk until it reaches the age you specify. With LVM 
(possibly depending on it's rules about how and when to cache - I admit I don't 
know a lot about tuning possibilities there) you could end up with issues like 
one of your users decides to do some analysis/extract a heap old data and ends 
up evicting the recent data from your cache and cause what you expected to be 
hot data to slow down. 

> Make it possible to move non-compacting sstables to slow/big storage in DTCS
> ----------------------------------------------------------------------------
>
>                 Key: CASSANDRA-8460
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-8460
>             Project: Cassandra
>          Issue Type: Improvement
>            Reporter: Marcus Eriksson
>            Assignee: Lerh Chuan Low
>            Priority: Major
>              Labels: doc-impacting, dtcs
>             Fix For: 4.x
>
>
> It would be nice if we could configure DTCS to have a set of extra data 
> directories where we move the sstables once they are older than 
> max_sstable_age_days. 
> This would enable users to have a quick, small SSD for hot, new data, and big 
> spinning disks for data that is rarely read and never compacted.



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