I have configured cassandra 1.1.4 to use row cache of 10GB ( the RAM on the machine is pretty big and hence the row cache size is high).  My heap settings are 8G and new heap size is 1600M. 

As I read from the forum and documentation, jna.jar allows to use non-heap memory for the row caches. 

The question I have is how is the configuration in cassandra.yaml for row_cache_size_in_mb interpreted? Is it referring to the non-heap setting or the memory used inside the heap to maintain book-keeping information about the non-heap memory ( as I gather from the postings that heap is indeed used to some extent while still using the non-heap memory for row caches). 

In short the question is whether the row_cache_size_in_mb can exceed the heap setting for cassandra 1.1.4 if jna.jar is present in the libs? 

Thanks for your time.