脚本完成后python垃圾收集时出现奇怪的线程错误

Question

我有一个 python 脚本，它同时使用多个 SSH 链接到多个远程服务器。有时当脚本完成时，我想在垃圾收集期间，我得到了这个异常：

Exception in thread Thread-7 (most likely raised during interpreter shutdown):
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 552, in __bootstrap_inner
  File "/usr/lib/python2.7/dist-packages/paramiko/transport.py", line 1574, in run
<type 'exceptions.AttributeError'>: 'NoneType' object has no attribute 'error'
Exception in thread Thread-5 (most likely raised during interpreter shutdown):
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 552, in __bootstrap_inner
  File "/usr/lib/python2.7/dist-packages/paramiko/transport.py", line 1574, in run
<type 'exceptions.AttributeError'>: 'NoneType' object has no attribute 'error'
Exception in thread Thread-4 (most likely raised during interpreter shutdown):
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 552, in __bootstrap_inner
  File "/usr/lib/python2.7/dist-packages/paramiko/transport.py", line 1574, in run
<type 'exceptions.AttributeError'>: 'NoneType' object has no attribute 'error'
Exception in thread Thread-1 (most likely raised during interpreter shutdown):
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 552, in __bootstrap_inner
  File "/usr/lib/python2.7/dist-packages/paramiko/transport.py", line 1574, in run
<type 'exceptions.AttributeError'>: 'NoneType' object has no attribute 'error'

我搜索了Exception in thread Thread-7 (most likely raised during interpreter shutdown)，发现有时在多线程脚本中杀死线程会导致此异常。这对我来说真的很奇怪，因为我的脚本中没有线程。另一方面，它似乎与paramiko 有关，我很确定我不使用线程来创建 SSH 链接；我只有多个打开的 shell 连接到多台服务器（可能不止一个 shell 连接到一台特定的服务器）。知道异常的来源吗？？

Answer 1

这似乎是 Paramiko 中的一个已知错误，请参阅：https://github.com/paramiko/paramiko/issues/17