I noticed that the stop time varies between somewhere around 30 seconds and 6 minutes.

While trying to catch the reason for I used this:

while true ; do pgrep -af manila-share >> out.txt ; echo -e "`date --rfc-3339=ns`\n"'------------' >> out.txt ; sleep 0.1 ; done


https://paste.ubuntu.com/p/jcsJF4WVmH/
------------
302430 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
302463 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
304498 watch --color -n1 systemctl status manila-share
2020-08-04 20:39:28.652242839+00:00
------------
302430 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
302463 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
304498 watch --color -n1 systemctl status manila-share
305575 systemctl disable manila-share
305576 /bin/sh /lib/systemd/systemd-sysv-install disable manila-share
305578 /usr/bin/perl /usr/sbin/update-rc.d manila-share defaults
2020-08-04 20:39:28.847391469+00:00
------------
302430 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
302463 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
304498 watch --color -n1 systemctl status manila-share
305575 systemctl disable manila-share
305576 /bin/sh /lib/systemd/systemd-sysv-install disable manila-share
305578 /usr/bin/perl /usr/sbin/update-rc.d manila-share defaults
305609 watch --color -n1 systemctl status manila-share
305610 sh -c systemctl status manila-share
305611 systemctl status manila-share
2020-08-04 20:39:29.040207067+00:00
------------
302430 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
302463 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
304498 watch --color -n1 systemctl status manila-share
305575 systemctl disable manila-share
305576 /bin/sh /lib/systemd/systemd-sysv-install disable manila-share
2020-08-04 20:39:29.265223464+00:00
------------
302430 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
302463 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
304498 watch --color -n1 systemctl status manila-share
305575 systemctl disable manila-share
305576 /bin/sh /lib/systemd/systemd-sysv-install disable manila-share
305619 /usr/bin/perl /usr/sbin/update-rc.d manila-share disable
2020-08-04 20:39:29.472259353+00:00
------------
302430 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
302463 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
304498 watch --color -n1 systemctl status manila-share
305575 systemctl disable manila-share
305576 /bin/sh /lib/systemd/systemd-sysv-install disable manila-share
305619 /usr/bin/perl /usr/sbin/update-rc.d manila-share disable
2020-08-04 20:39:29.667573240+00:00
------------
302430 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
302463 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
304498 watch --color -n1 systemctl status manila-share
305575 systemctl disable manila-share
2020-08-04 20:39:29.893292804+00:00
------------
302430 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
302463 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
304498 watch --color -n1 systemctl status manila-share
305575 systemctl disable manila-share
2020-08-04 20:39:30.087195853+00:00
------------
302430 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
302463 /usr/bin/python3 /usr/bin/manila-share --config-file=/etc/manila/manila.conf --log-file=/var/log/manila/manila-share.log
304498 watch --color -n1 systemctl status manila-share
305575 systemctl disable manila-share
2020-08-04 20:39:30.297277618+00:00
------------
304498 watch --color -n1 systemctl status manila-share
2020-08-04 20:39:30.548159630+00:00
------------