Java's garbage collected heap is not the full extent of memory used by Cassandra. Cassandra can use as much memory as you can throw at it. File system cache, i

Java's garbage collected heap is not the full extent of memory used by Cassandra. Cassandra can use as much memory as you can throw at it. File system cache, in process decompressed page cache, key and row cache, off heap memtables etc. There are several different mechanisms for using memory that isn't on the garbage collected heap. ^ This is not a qualitative assessment of how Cassandra uses memory.