Hi @sourceminer,
Perhaps others have found better ways to do this...
But the most interesting stuff I have found is described here. The disadvantage is that you need to start Node-RED via ClinicJs, and the result is only analyzed after you close it again. So it is no real time monitoring that you can attach to a running Node-RED instance unfortunately.
From what I have read so far, I don't think it is possible to do live monitoring of cpu/memory per node or flow. In case you would like to digg in technical debt, see here for more background info. Warning: it is no bedtime literature 
But of course I might be mistaken...
Bart
