I had no trouble reproducing this on my Ubuntu Feisty box. It turns out that wxPython leaks a dictionary for every object whose class subclasses a Wx class. There is a fix for this that made it into wxPython-2.8.3.0: http://cvs.wxwidgets.org/viewcvs.cgi/wxWidgets/wxPython/src/helpers.cpp.diff?r1=1.145&r2=1.145.4.1 <http://cvs.wxwidgets.org/viewcvs.cgi/wxWidgets/wxPython/src/helpers.cpp.diff?r1=1.145&r2=1.145.4.1> I have verified this on my source-built wxPython-2.8.4.0. If I remove this line, I can reproduce the reference leak. ** I would recommend that anyone using a wxPython-2.8.x prior to wxPython-2.8.4 should upgrade. There are binary packages available for a number of distributions on wxpython.org. ** As an aside, I filed a bug for this on Ubuntu launchpad. I don't know if this qualifies for the kind of fix they would normally make as a maintenance release. Promisingly, my bug was confirmed within about five minutes of filing it. https://bugs.launchpad.net/ubuntu/+source/wxwidgets2.8/+bug/124381 <https://bugs.launchpad.net/ubuntu/+source/wxwidgets2.8/+bug/124381> Cheers, Mike Eric Firing wrote: > Michael Droettboom wrote: >> Interesting... >> >> When you get a chance, would you mind running the attached script? >> This is how I was finding object leaks before. It takes a single >> commandline argument that is the number of iterations. Can you send >> me the outputs from 1 and 2 iterations? That way we should be able >> to see what type of object is being leaked, which is a good first step. > > efiring@manini:~/programs/py/mpl/tests$ python memleak_gui_wx.py 1 > 75891 76010 > *** <class 'wx._core.PySimpleApp'> > *** <class 'wx._core._wxPyDeadObject'> > > uncollectable list: [] > > efiring@manini:~/programs/py/mpl/tests$ python memleak_gui_wx.py 2 > GnomePrintCupsPlugin-Message: The ppd file for the CUPS printer > Dell424 could not be loaded. > GnomePrintCupsPlugin-Message: The ppd file for the CUPS printer pslj4m > could not be loaded. > 75891 76014 > *** <class 'wx._core.PySimpleApp'> > *** <class 'wx._core._wxPyDeadObject'> > > uncollectable list: [] > > > Eric >