root@lists1004:~ $ sudo systemctl stop exim4
root@lists1004:~ $ ps auxf|rg -i exim
mtail        836  0.4  0.0 3308356 27304 ?       Ssl  May26 719:22 /usr/bin/mtail --progs /etc/mtail --logtostderr --address :: --port 3903 --logs /var/log/exim4/mainlog,/var/log/mailman/smtp,/var/log/mailman/subscribe -disable_fsnotify
root     1201963  0.0  0.0   9124  5960 pts/0    S+   10:20   0:00                      \_ rg -i exim
root     1193401  0.0  0.0  47848 27964 ?        S    10:14   0:00 /usr/sbin/exim4 -q
root     1193491  0.0  0.0  47848 22400 ?        S    10:14   0:00  \_ /usr/sbin/exim4 -q
Debian-+ 1193492  0.0  0.0  48004 24288 ?        S    10:14   0:00      \_ /usr/sbin/exim4 -q
root     1200450  0.8  0.0  47840 28080 ?        S    10:19   0:00 /usr/sbin/exim4 -q
root     1201885  0.0  0.0  47840 22524 ?        S    10:20   0:00  \_ /usr/sbin/exim4 -q
Debian-+ 1201886  0.0  0.0  47844 23988 ?        S    10:20   0:00      \_ /usr/sbin/exim4 -q
root     1201639  1.2  0.0  47844 28008 ?        S    10:20   0:00 /usr/sbin/exim4 -q
Debian-+ 1201964  0.0  0.0      0     0 ?        R    10:20   0:00  \_ [exim4]