maxima is eating up all the memory

edit

If you are just interested in using some functionality that maxima offers on a sage expression, then maxima_methods is probably an outdated way of doing so presently: it still uses a text-based interface to maxima, whereas we have maxima_lib nowadays.

If you have a symbolic expression F and do

F._maxima_().exponentialize()._sage_()

you should get basically the same result as

F.maxima_methods().exponentialize()

but via the more efficient maxima_lib interface. That doesn't involve a separate process either, so killing sage will just do the trick. Perhaps maxima_methods needs to be migrated to use maxima_lib, but since the only thing it does is convert the expression back to sage after the method call, it's hardly worth supporting in the first place.