Python Tox运行通常需要30秒

Tox在几周前运行良好，但我回到了一个使用Tox运行测试的项目，现在运行总是需要30秒。我原以为对项目所做的更改可能会有问题，但我在其他项目中尝试过tox（甚至是hello world测试），它们都需要30秒才能运行

$ time tox
GLOB sdist-make: /private/tmp/dependency_manager/setup.py
py27 inst-nodeps: /private/tmp/dependency_manager/.tox/dist/dependencyManager-1.3.6.zip
py27 installed: boto==2.41.0,boto3==1.3.1,botocore==1.4.33,dependencyManager==1.3.6,docutils==0.12,funcsigs==1.0.2,futures==3.0.5,jmespath==0.9.0,mock==2.0.0,nose2==0.6.5,pbr==1.10.0,python-dateutil==2.5.3,six==1.10.0,troposphere==1.6.0
py27 runtests: PYTHONHASHSEED='3107006541'
py27 runtests: commands[0] | nose2
/private/tmp/dependency_manager/.tox/py27/lib/python2.7/site-packages/troposphere/dynamodb.py:10: UserWarning: This module is outdated and will be replaced with troposphere.dynamodb2. Please see the README for instructions on how to prepare for this change.
  warnings.warn("This module is outdated and will be replaced with "
.....................
----------------------------------------------------------------------
Ran 21 tests in 0.020s

OK
_____________________________________________________________________________________________ summary ______________________________________________________________________________________________
  py27: commands succeeded
  congratulations :)
tox  1,67s user 0,43s system 6% cpu 32,192 total

现在是一个完全不同的项目

$ time tox
py27 recreate: /Users/jose.armesto/dev/dredd/.tox/py27
py27 installdeps: nose, mock, coverage >= 3.3
py27 installed: coverage==4.1,funcsigs==1.0.2,mock==2.0.0,nose==1.3.7,pbr==1.10.0,six==1.10.0
py27 runtests: PYTHONHASHSEED='1261821084'
py27 runtests: commands[0] | nosetests --with-coverage --cover-branches
....
Name                  Stmts   Miss Branch BrPart  Cover
-------------------------------------------------------
funcsigs.py             432    357    194      0    12%
funcsigs/version.py       1      0      0      0   100%
mock.py                   4      0      0      0   100%
mock/mock.py           1373    987    578     44    23%
pbr.py                    0      0      0      0   100%
pbr/version.py          218    116     66     16    42%
six.py                  444    218    134     21    46%
dredd.py                  0      0      0      0   100%
dredd/discovery.py        0      0      0      0   100%
dredd/dredd.py           28      0     18      1    98%
dredd/instance.py         9      1      0      0    89%
-------------------------------------------------------
TOTAL                  2509   1679    990     82    28%
----------------------------------------------------------------------
Ran 4 tests in 0.026s

OK
_____________________________________________________________________________________________ summary ______________________________________________________________________________________________
  py27: commands succeeded
  congratulations :)
tox  3,67s user 0,87s system 12% cpu 37,636 total

这就像在30秒时超时一样，然后它就可以正常运行测试了。 我尝试使用

ls-lah

作为命令和配置文件tox，我得到了这些结果

我正在运行OSX Yosemite 10.10.5 Python和tox版本

$ python --version
Python 2.7.10

$ tox --version
2.3.1 imported from /Library/Python/2.7/site-packages/tox/__init__.pyc

---

我曾经尝试过使用和不使用

setup.py

的项目，使用的环境或多或少，我总是得到同样的慢时间。有人知道发生了什么以及如何修复吗？

删除$HOME/中安装的旧软件包。tox解决了这个问题。这30秒似乎是由于boto超时，其中一些软件包使用了boto。我不知道为什么会这样