"Too many open files" in test runs on Python 3.3 #3315
Description
The OSX testing juggernaut rolls on. For tests on Python 3.3.5, I am getting multiple (> 400) test errors related to "Too many open files":
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ERROR: matplotlib.tests.test_mathtext.test_mathtext_cm_37.test
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Traceback (most recent call last):
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/nose/case.py", line 198, in runTest
self.test(*self.arg)
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/matplotlib/testing/decorators.py", line 51, in failer
result = f(*args, **kwargs)
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/matplotlib/testing/decorators.py", line 183, in do_test
figure.savefig(actual_fname, **self._savefig_kwarg)
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/matplotlib/figure.py", line 1470, in savefig
self.canvas.print_figure(*args, **kwargs)
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/matplotlib/backend_bases.py", line 2192, in print_figure
**kwargs)
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/matplotlib/backends/backend_pdf.py", line 2475, in print_pdf
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/matplotlib/backends/backend_pdf.py", line 525, in close
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/matplotlib/backends/backend_pdf.py", line 628, in writeFonts
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/matplotlib/backends/backend_pdf.py", line 798, in embedTTF
OSError: [Errno 24] Too many open files: '/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/matplotlib/mpl-data/fonts/ttf/cmr10.ttf'
See:
- https://s3.amazonaws.com/archive.travis-ci.org/jobs/30947790/log.txt
- https://s3.amazonaws.com/archive.travis-ci.org/jobs/30947803/log.txt
I wasn't getting this failure for the multiprocess tests on previous Python 3.3 runs (which will have been testing a different commit on the 1.4.x branch):
https://s3.amazonaws.com/archive.travis-ci.org/jobs/30794971/log.txt
I assume this is because the multiprocess tests were each only using a smaller number of open files per process.
Any ideas why this should be happening for Python 3.3 specifically, not 2.7 or 3.4?