First timeout:
http://buildbot.python.org/all/builders/x86%20Ubuntu%20Shared%203.x/builds/11358

This build was only triggered by one changeset 0b99d7043a99: "Issue #23694: Enhance _Py_open(), it now raises exceptions".

 * _Py_open() now raises exceptions on error. If open() fails, it raises an OSError with the filename.
 * _Py_open() now releases the GIL while calling open()
 * Add _Py_open_noraise() when _Py_open() cannot be used because the GIL is not held

Example of subprocess timeout:
---
Timeout (1:00:00)!
Thread 0x55aaedc0 (most recent call first):
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/subprocess.py", line 1502 in _try_wait
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/subprocess.py", line 1552 in wait
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/test_subprocess.py", line 58 in tearDown
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/case.py", line 580 in run
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/case.py", line 625 in __call__
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/suite.py", line 122 in run
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/suite.py", line 84 in __call__
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/suite.py", line 122 in run
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/suite.py", line 84 in __call__
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/runner.py", line 176 in run
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/support/__init__.py", line 1773 in _run_suite
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/support/__init__.py", line 1807 in run_unittest
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/test_subprocess.py", line 2532 in test_main
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/regrtest.py", line 1284 in runtest_inner
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/regrtest.py", line 967 in runtest
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/regrtest.py", line 763 in main
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/regrtest.py", line 1568 in main_in_temp_cwd
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/__main__.py", line 3 in <module>
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/runpy.py", line 85 in _run_code
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/runpy.py", line 170 in _run_module_as_main
make: *** [buildbottest] Error 1
---

Example of multiprocessing timeout:
---
[240/393] test_multiprocessing_spawn
Timeout (1:00:00)!
Thread 0x68fddb40 (most recent call first):
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/connection.py", line 379 in _recv
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/connection.py", line 407 in _recv_bytes
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/connection.py", line 250 in recv
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/managers.py", line 717 in _callmethod
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/managers.py", line 955 in wait
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/_test_multiprocessing.py", line 834 in f
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/threading.py", line 871 in run
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/threading.py", line 923 in _bootstrap_inner
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/threading.py", line 891 in _bootstrap

Thread 0x58a5ab40 (most recent call first):
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/connection.py", line 379 in _recv
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/connection.py", line 407 in _recv_bytes
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/connection.py", line 250 in recv
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/managers.py", line 717 in _callmethod
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/managers.py", line 955 in wait
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/_test_multiprocessing.py", line 834 in f
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/threading.py", line 871 in run
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/threading.py", line 923 in _bootstrap_inner
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/threading.py", line 891 in _bootstrap

(...)

Thread 0x55aaedc0 (most recent call first):
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/connection.py", line 379 in _recv
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/connection.py", line 407 in _recv_bytes
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/connection.py", line 250 in recv
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/managers.py", line 717 in _callmethod
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/multiprocessing/managers.py", line 943 in acquire
  File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/_test_multiprocessing.py", line 933 in test_notify_all
  ...
---