Re: [Matplotlib-users] Matplotlib eating memory

[Benjamin R. <ben...@ou...>]

On Thu, Oct 10, 2013 at 9:05 AM, Martin MOKREJŠ <mmo...@gm...> wrote:

> Hi,
>   rendering some of my charts takes almost 50GB of RAM. I believe below is
> a stracktrace
> of one such situation when it already took 15GB. Would somebody comments
> on what is
> matplotlib doing at the very moment? Why the recursion?
>
>   The charts had to have 262422 data points in a 2D scatter plot, each
> point has assigned
> its own color. They are in batches so that there are 153 distinct colors
> but nevertheless,
> I assigned to each data point a color value. There are 153 legend items
> also (one color
> won't be used).
>
> ^CTraceback (most recent call last):
> ...
>     _figure.savefig(filename, dpi=100)
>   File "/usr/lib64/python2.7/site-packages/matplotlib/figure.py", line
> 1421, in savefig
>     self.canvas.print_figure(*args, **kwargs)
>   File "/usr/lib64/python2.7/site-packages/matplotlib/backend_bases.py",
> line 2220, in print_figure
>     **kwargs)
>   File
> "/usr/lib64/python2.7/site-packages/matplotlib/backends/backend_agg.py",
> line 505, in print_png
>     FigureCanvasAgg.draw(self)
>   File
> "/usr/lib64/python2.7/site-packages/matplotlib/backends/backend_agg.py",
> line 451, in draw
>     self.figure.draw(self.renderer)
>   File "/usr/lib64/python2.7/site-packages/matplotlib/artist.py", line 54,
> in draw_wrapper
>     draw(artist, renderer, *args, **kwargs)
>   File "/usr/lib64/python2.7/site-packages/matplotlib/figure.py", line
> 1034, in draw
>     func(*args)
>   File "/usr/lib64/python2.7/site-packages/matplotlib/artist.py", line 54,
> in draw_wrapper
>     draw(artist, renderer, *args, **kwargs)
>   File "/usr/lib64/python2.7/site-packages/matplotlib/axes.py", line 2086,
> in draw
>     a.draw(renderer)
>   File "/usr/lib64/python2.7/site-packages/matplotlib/artist.py", line 54,
> in draw_wrapper
>     draw(artist, renderer, *args, **kwargs)
>   File "/usr/lib64/python2.7/site-packages/matplotlib/collections.py",
> line 718, in draw
>     return Collection.draw(self, renderer)
>   File "/usr/lib64/python2.7/site-packages/matplotlib/artist.py", line 54,
> in draw_wrapper
>     draw(artist, renderer, *args, **kwargs)
>   File "/usr/lib64/python2.7/site-packages/matplotlib/collections.py",
> line 276, in draw
>     offsets, transOffset, self.get_facecolor(), self.get_edgecolor(),
>   File "/usr/lib64/python2.7/site-packages/matplotlib/collections.py",
> line 551, in get_edgecolor
>     return self._edgecolors
> KeyboardInterrupt
> ^CError in atexit._run_exitfuncs:
> Traceback (most recent call last):
>   File "/usr/lib64/python2.7/atexit.py", line 24, in _run_exitfuncs
>     func(*targs, **kargs)
>   File "/usr/lib64/python2.7/site-packages/matplotlib/_pylab_helpers.py",
> line 90, in destroy_all
>     gc.collect()
> KeyboardInterrupt
> Error in sys.exitfunc:
> Traceback (most recent call last):
>   File "/usr/lib64/python2.7/atexit.py", line 24, in _run_exitfuncs
>     func(*targs, **kargs)
>   File "/usr/lib64/python2.7/site-packages/matplotlib/_pylab_helpers.py",
> line 90, in destroy_all
>     gc.collect()
> KeyboardInterrupt
>
> ^C
>
>
> Clues what is the code doing? I use mpl-1.3.0.
> Thank you,
> Martin
>
>
Unfortunately, that stacktrace isn't very useful. There is no recursion
there, but rather the perfectly normal drawing of the figure object that
has a child axes, which has child collections which have child artist
objects.

Without the accompanying code, it would be difficult to determine where the
memory hog is.

Ben Root