Using the asyncio.create_subprocess_exec, generates lost of internal error messages. These messages are:

Exception ignored when trying to write to the signal wakeup fd:
BlockingIOError: [Errno 11] Resource temporarily unavailable

Getting the messages depeneds on how many subprocesses are active at the same time. In my system (Debian 7, kernel 3.2.0-4-amd64, python 3.4.1), with 3 or less processes at the same time I don't see any problem, but with 4 or more I got lot of messages.

On the other hand, these error messages seem to be innocuous, as no exception seems to be raised.

Attached is a test script that shows the problem.

It is run as:
bin/python3.4 test_subprocess_error.py <MAX_PROCESSES> <ITERATIONS>

it requires to have the du command.


Let me know if there are any (conceptual) mistakes in the attached code.