On Thu, Nov 14, 2013 at 10:05 AM, J. Ryan Earl <oss@jryanearl.us> wrote:
* Cassandra 2.0.2 has a lot of improvements, consider upgrading.  We noticed improved heap usage compared to 2.0.2

https://engineering.eventbrite.com/what-version-of-cassandra-should-i-run/

And especially if you're using Level Compaction / LCS :

https://issues.apache.org/jira/browse/CASSANDRA-6284 
"Wrong tracking of minLevel in Leveled Compaction Strategy causing serious performance problems"

tl;dr - don't upgrade to 2.0.2 in production.

=Rob