You can run your command(s) via
systemd-run --scope. This creates a transient (ie temporary) cgroup for your command. You can then modify the cgroup to your needs.
systemd-cgls to find your process in the cgroup hierarchy under
According to the systemd-run manpage
systemd-run may be used to create and start a transient .service or a transient .timer or a .scope unit and run the specified COMMAND in it.
You can also specify restrictions for your unit via the
systemd-run command by using the
--property flag (more than once is allowed). For available properties you can check with the sytemd.resource-control manpage.
If you want to set properties later on, you can use
Keep in mind that it's a good idea to provide a name for your unit with the
--unit=yourname flag, so you can easily access it.
There is a very good text about the new control group interface, which I strongly recommend.
Also, the Red Hat Enterprise Linux 7
Resource Management and Linux Containers Guide provides a very clear description of how to use cgroups wirh systemd.