Thank you for tracking this down, Mike. Darren
On Wednesday 21 November 2007 11:17:04 am Michael Droettboom wrote: > It seems that the set of callbacks held by the Axis objects was not > being cleared by cla(). > > This has been fixed in SVN r4404, and does seem to correct your example > script. I'd appreciate a sanity check by the other developers to make > sure that change makes sense -- i.e. that the Axis callbacks don't > really need to stick around beyond the call to cla() for any reason I'm > not aware of. > > An alternative and more general solution would be to change the > implementation of CallbackRegistry so it uses a WeakValueDictionary, so > that it won't keep callback targets alive that have otherwise been > orphaned. But I can't decide whether that is a good thing or would just > hide easily fixed errors. > > Cheers, > Mike > > Michael Droettboom wrote: > > I should have some time today to look at this, unless any other > > developers already know an obvious solution. > > > > Cheers, > > Mike > > > > Darren Dale wrote: > >> I have been working on an application which is basically a dressed up > >> version of embedding_in_qt4.py. I have two canvases, one is just a plot, > >> the other an image with a colorbar, both of which should get updated > >> about once a second as data is acquired. I noticed that for larger > >> images, it was taking longer to update the canvases as time went on. > >> > >> Attached is a script that demonstrates the problem (png's are also > >> attached for those who dont have PyQt4). At each timeout, I check the > >> time, generate a new random array, update the image's data, draw it, > >> collect garbage, and check the time again. The plot in the upper window > >> shows how long it took to update the image canvas as a function of > >> iteration number. > >> > >> When the image has a colorbar, the time to update the image canvas > >> increases linearly, about 0.3 ms/iteration. This can really add up: > >> after 20,000 iterations it takes about 5-6 seconds to update the image > >> canvas. If I comment out the line that creates the colorbar (line 64), > >> the time to update the image canvas does not increase. > >> > >> A couple other observations and benchmarks from this test: > >> > >> * The intercept for the update time with a color bar was 0.17 seconds > >> * With the colorbar enabled but garbage collection turned off, the > >> application slowly consumed memory, roughly 12KB/iteration > >> * Updating an image without a colorbar took 0.1 seconds per iteration, > >> and did not increase > >> * Turning off both garbage collection and the colorbar decreased the > >> update time to 0.043 seconds, with maybe 1.7 KB/iteration increase in > >> memory usage. > >> > >> I don't know if I'll get a chance to dig any further into this in the > >> next two weeks. For now, I'll just disable the colorbar in my > >> application. > >> > >> Darren > >> > >> > >> ------------------------------------------------------------------------ > >> > >> > >> ------------------------------------------------------------------------ > >> > >> > >> ------------------------------------------------------------------------ > >> > >> ------------------------------------------------------------------------ > >>- This SF.net email is sponsored by: Microsoft > >> Defy all challenges. Microsoft(R) Visual Studio 2005. > >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > >> > >> > >> ------------------------------------------------------------------------ > >> > >> _______________________________________________ > >> Matplotlib-devel mailing list > >> Matplotlib-devel@lists.sourceforge.net > >> https://lists.sourceforge.net/lists/listinfo/matplotlib-devel -- Darren S. Dale, Ph.D. [EMAIL PROTECTED] ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
