Apart from the suggestion of Ramaraju, to make it simple,
- Stop CM using adcmctl.sh
- Kill any FND processes
- Run cmclean
- Start services.
These are usual issues so I believe not in wasting much time in these. cmclean is a certified non-destructive script.
If we run cmclean, what happen to all scheduled jobs? They were removed or still in schedule status?
cmclean will only clean up the fnd_concurrent_processes. Currently running requests will be impacted but not the scheduled/pending ones. So you can proceed.