There are many runner processes and var/queue/out/ is currently empty.
mailman 196777 0.0 1.1 103052 86488 ? S 06:28 0:05 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=archive:0:1 mailman 196779 0.0 1.1 105888 89116 ? S 06:28 0:04 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=bounces:0:1 mailman 196780 0.0 1.1 103048 86584 ? S 06:28 0:05 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=command:0:1 mailman 196782 0.0 1.1 103048 86464 ? S 06:28 0:05 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=in:0:1 mailman 196783 0.0 1.1 176792 86684 ? Sl 06:28 0:02 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=lmtp:0:1 mailman 196784 0.0 1.1 103048 86536 ? S 06:28 0:05 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=out:0:1 mailman 196785 0.0 1.1 103060 86420 ? S 06:28 0:05 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=pipeline:0:1 mailman 196786 0.0 1.2 108284 91896 ? S 06:28 0:05 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=rest:0:1 mailman 196787 0.0 1.1 103056 86588 ? S 06:28 0:01 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=retry:0:1 mailman 196788 0.0 1.1 105756 88656 ? S 06:28 0:02 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=task:0:1 mailman 196794 0.0 1.1 103048 86548 ? S 06:28 0:05 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=virgin:0:1 mailman 196799 0.0 1.1 103044 86596 ? S 06:28 0:05 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=digest:0:1 mailman 196945 0.0 1.0 111260 82884 ? S 06:28 0:00 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=rest:0:1 mailman 196946 0.0 1.0 111260 82756 ? S 06:28 0:00 /opt/mailman/venv/bin/python3 /opt/mailman/venv/bin/runner -C /etc/mailman3/mailman.cfg --runner=rest:0:1