Stepping slow in debug when lots of variables

Hi,

When my variables in a namespace take up a lot of memory (numpy arrays or images, for example), it takes a long time to step through my program in debug mode.  Sometimes it takes up to 10 seconds to repopulate the variables window.  What's worse, I can't continue stepping through the code until it is populated.  Is there a way to decrease the introspection level, or create a timeout, or something of the sort?

Thanks.