We have some issue having a high read throughput. I wanted to alleviate things by turning the row cache ON.

I set the row cache to 200 on one node and enable caching 'ALL' on the 3 most read CF. There is the effect this operation had on my JVM: http://img692.imageshack.us/img692/4171/datastaxopscenterr.png

It looks like the row cache was somehow stored in-heap. I looked at my cassandra.yaml and I have the following configuration: row_cache_provider: SerializingCacheProvider (which should be enough to store row cache off-heap as described above in this file: "SerializingCacheProvider serialises the contents of the row and stores it in native memory, i.e., off the JVM Heap")

What's wrong ?