and for now I removed these:
Code:
pla-3-TW:/home/pla # systemctl disable btrfsmaintenance-refresh.service
Removed /etc/systemd/system/multi-user.target.wants/btrfsmaintenance-refresh.path.
Removed /etc/systemd/system/multi-user.target.wants/btrfsmaintenance-refresh.service.
pla-3-TW:/home/pla # systemctl disable ModemManager.service
Removed /etc/systemd/system/dbus-org.freedesktop.ModemManager1.service.
Removed /etc/systemd/system/multi-user.target.wants/ModemManager.service.
pla-3-TW:/home/pla # systemctl disable apparmor.service
Removed /etc/systemd/system/multi-user.target.wants/apparmor.service.
pla-3-TW:/home/pla #