Подавить сообщения в /var/log/messages вида: Created slice, User Slice of nginx и т.п.

To suppress these log entries in /var/log/messages, create a discard filter with rsyslog, e.g., run the following command:

# echo 'if $programname == "systemd" and ($msg contains "Starting Session" or $msg contains "Started Session" or $msg contains "Created slice" or $msg contains "Starting user-" or $msg contains "Starting User Slice of" or $msg contains "Removed session" or $msg contains "Removed slice User Slice of" or $msg contains "Stopping User Slice of") then stop' >/etc/rsyslog.d/ignore-systemd-session-slice.conf

Then restart the rsyslog service

# systemctl restart rsyslog

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