memory overhead question

[Luke H. Crouch]

when we start our cluster up with default settings (DataMemory: 80000k, IndexMemory:
24000k), and check the memory usage on our different nodes, it shows ndbd size as 2395M!
and the machine is using 2G memory, and 1G of swap! 

are these numbers overhead with only 80M of memory allocated to data? how much memory is
required other than the memory dedicated to data via DataMemory setting?

thanks,
-L