Deadlock with logging multiprocess/multithread python script

Question

I am facing the problem with collecting logs from the following script. Once I set up the SLEEP_TIME to too \"small\" value, the LoggingThread threads somehow b

Answer 1

This is probably bug 6721.

The problem is common in any situation where you have locks, threads and forks. If thread 1 had a lock while thread 2 calls fork, in the forked process, there will only be thread 2 and the lock will be held forever. In your case, that is logging.StreamHandler.lock.

A fix can be found here (permalink) for the logging module. Note that you need to take care of any other locks, too.