* Handle more signals
* Flush buffers before exiting process
This ensures log messages aren't lost
* Restart process before jobs have finished
If there is a very log running job it can cause service restart to
take over 5 minutes.
We tweak the order of things to make sure that running processes
continue, but nothing more is scheduled.
The worst case impact is that a pollling/discovery job gets
scheduled twice, but this should not be a big issue - this should
only occur at most once per day.
* Remove python 3.8 feature
* Ensure that processes from the previous invocation are reaped
* Correct typo's
* Attach subprocess descriptors to /dev/null
Occasionally, PHP would throw a fit and crash when its stdout went
away. To avoid this, we attach stdout to devnull.
This means we lost output of daily.sh - but this is already recorded
in $LOGDIR/daily.log
* Don't immediately schedule long running jobs
To avoid the situation where the maintenance reload happens or a sighup,
then a second long running job is immediately started, we wait
(`last_[poll/discovery]_timetaken` * 1.25) seconds before scheduling
any jobs.
* Add `psutil` to requirements
* Add support for "systemctl reload" to the unit files
* Add a fallback for systems that don't have psutil
* Reduce CPU load when psutil is not installed
* Don't avoid double polling by extending the timeout
This shouldn't happen due to locks
* Remove fallback option
* Remove extra variable
* Fix issue introduced during rebase
* Fix issue introduced when fixing issue introduced during rebase
* Make psutil optional
Currently has a file handle leak (and will eventually run out of handles) related to the self update process.
Either need to fix that or rip out self-update and leave that up to cron or something.
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