Dispatcher refactoring to get pg_notify publish payload
as separate method
Refactor periodic module under dispatcher entirely
Use real numbers for schedule reference time
Run based on due_to_run method
Review comments about naming and code comments
* Introduce new method in settings, import in-line w NOQA mark
* Further refine the app_name to use shorter service names like dispatcher
* Clean up listener logic, change some names
I have a hunch that our usage of a daemon thread is causing import lock
contention related to https://github.com/ansible/awx/issues/5617
We've encountered similar issues before with threads across dispatcher
processes at fork time, and cpython has had bugs like this in recent
history:
https://bugs.python.org/issue38884
My gut tells me this might be related.
The prior implementation - based on celerybeat - ran its code in
a process (not a thread), and the timing of that merge matches the
period of time we started noticing issues.
Currently testing it to see if it resolves some of the issues we're
seeing.
