Gaetan Bisson wrote:

From version 207 on, systemd will not apply the settings from `/etc/sysctl.conf`

anymore: it will only apply those from `/etc/sysctl.d/*`. Since the settings of our `/etc/sysctl.conf` shipped by procps-ng have become kernel defaults anyway, we have decided to deprecate this file.

Upon upgrading to procps-ng-3.3.8-3, you will be prompted to move any changes you made to `/etc/sysctl.conf` under `/etc/sysctl.d`. The easiest way to do this is to run:

pacman -Syu

mv /etc/sysctl.conf.pacsave /etc/sysctl.d/99-sysctl.conf

If you never customized `/etc/sysctl.conf`, you have nothing to do.

URL: https://www.archlinux.org/news/deprecation-of-etcsysctlconf/