Information about usage of multiple cores

How can I view how many cores are being used from MATLAB and the according percentage? I would like to know if there is a way to profile the code in order to retrieve this information

[jgg]

This is a good question. I have always used the system monitor top to check this on my Linux system. I know the built in profiler does not help in giving insight into jobs, so I would be interested in an answer to this as well.