This has been happening recently on our Windows Server 2008 buildbot:


======================================================================
FAIL: test_first_completed (test.test_concurrent_futures.ThreadPoolWaitTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "c:\buildslave-py3k\3.x.curtin-win2008-amd64\build\lib\test\test_concurrent_futures.py", line 252, in test_first_completed
    self.assertEqual(set([future1]), done)
AssertionError: Items in the second set but not the first:
<Future at 0x19899f60 state=finished raised AssertionError>

======================================================================
FAIL: test_first_exception (test.test_concurrent_futures.ThreadPoolWaitTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "c:\buildslave-py3k\3.x.curtin-win2008-amd64\build\lib\test\test_concurrent_futures.py", line 293, in test_first_exception
    self.assertEqual(set([future1, future2]), finished)
AssertionError: Items in the second set but not the first:
<Future at 0x164e5878 state=finished raised AssertionError>

======================================================================
FAIL: test_first_exception_some_already_complete (test.test_concurrent_futures.ThreadPoolWaitTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "c:\buildslave-py3k\3.x.curtin-win2008-amd64\build\lib\test\test_concurrent_futures.py", line 323, in test_first_exception_some_already_complete
    future1]), finished)
AssertionError: Items in the second set but not the first:
<Future at 0x16f9b948 state=finished raised AssertionError>

======================================================================
FAIL: test_timeout (test.test_concurrent_futures.ThreadPoolWaitTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "c:\buildslave-py3k\3.x.curtin-win2008-amd64\build\lib\test\test_concurrent_futures.py", line 442, in test_timeout
    future1]), finished)
AssertionError: Items in the second set but not the first:
<Future at 0xd0efe28 state=finished raised AssertionError>


(see e.g. http://www.python.org/dev/buildbot/all/builders/AMD64%20Windows%20Server%202008%203.x/builds/306/steps/test/logs/stdio )

What's the best way for me to test this? The problem occurs on a Windows-only code path but there is not enough information for me to debug it.

Should I check-in some additional diagnostics, wait for the buildbot to run, collect my data and then rollback my change?

Or can I run code on the buildbot directly?

You can create a branch, checkin to that branch, then specify that a specific buildbot runs your branch. See the "force build" page of a build slave.

Additionally, I can give you access to my build slave, the Windows Server 2008 one, but that may take a few days due to the holiday weekend.

I'm good, thanks Brian C.

<br/>

It looks like SetEvent is failing with ERROR_INVALID_HANDLE.
CRITICAL:root:SetEvent(2044) failed with 0, GetLastError() = 6
CRITICAL:root:SetEvent(2064) failed with 0, GetLastError() = 6
CRITICAL:root:SetEvent(2220) failed with 0, GetLastError() = 6
CRITICAL:root:SetEvent(1576) failed with 0, GetLastError() = 6
CRITICAL:root:SetEvent(2284) failed with 0, GetLastError() = 6
CRITICAL:root:SetEvent(2168) failed with 0, GetLastError() = 6
CRITICAL:root:SetEvent(2264) failed with 0, GetLastError() = 6
CRITICAL:root:SetEvent(1588) failed with 0, GetLastError() = 6
CRITICAL:root:SetEvent(2240) failed with 0, GetLastError() = 6

Now to figure out why...

Fixed in r87673.