==== Default Slices ====

  * -.slice — the root slice;
  * system.slice — the default place for all system services;
  * user.slice — the default place for all user sessions;
  * machine.slice — the default place for all virtual machines and Linux containers.

==== CG Baum anzeigen ====
  # systemd-cgls
  # systemd-cgtop

==== Slices anzeigen ====
  # systemctl -t slice

==== Resource Controller ====

Available Controllers in Red Hat Enterprise Linux 7

  * blkio — sets limits on input/output access to and from block devices;
  * cpu — uses the CPU scheduler to provide cgroup tasks an access to the CPU. It is mounted together with the cpuacct controller on the same mount;
  * cpuacct — creates automatic reports on CPU resources used by tasks in a cgroup. It is mounted together with the cpu controller on the same mount;
  * cpuset — assigns individual CPUs (on a multicore system) and memory nodes to tasks in a cgroup;
  * devices — allows or denies access to devices for tasks in a cgroup;
  * freezer — suspends or resumes tasks in a cgroup;
  * memory — sets limits on memory use by tasks in a cgroup, and generates automatic reports on memory resources used by those tasks;
  * net_cls — tags network packets with a class identifier (classid) that allows the Linux traffic controller (the tc command) to identify packets originating from a particular cgroup task;
  * perf_event — enables monitoring cgroups with the perf tool;
  * hugetlb — allows to use virtual memory pages of large sizes, and to enforce resource limits on these pages.

==== Unit Parameter aendern ====
  # systemctl set-property <unit-name> <parameter>=<value>
  # systemctl set-property httpd.service CPUShares=600 MemoryLimit=500M
  # systemctl set-property --runtime httpd.service CPUShares=600 MemoryLimit=500M # temporary change 
Änderungen an schon bestehenden Units werden persistent!

=== Unit Parameter ===

^Parameter                                        ^Default^Beschreibung                                               ^
|CPUAccounting=true                               |--     |CPUAccounting anschalten                                   |
|CPUWeight=value                                  |100    |CPU Belegung                                               |
|MemoryAccounting=true                            |--     |Speicherverbrauch ueberwachung anschalten                  |
|MemoryLimit=value                                |--     |Speicherverbrauch (K,M,G,T)                                |
|BlockIOAccounting=true                           |--     |BlockIO Accounting anschalten                              |
|BlockIOWeight=value                              |100    |generische IO Prio (100 < Wert < 1000)                     |
|BlockIODeviceWeight=device_name value            |100    |IO Prio fuer Geraet                                        |
|BlockIOReadBandwidth=device_name value           |--     |Lese-Bandbreite pro Sekunde (K,M,G,T)                      |
|BlockIOWriteBandwidth=device_name value          |--     |Schreib-Bandbreite pro Sekunde (K,M,G,T)                   |
|DeviceAllow=device_name options                  |--     |Zugriff (r,w,m) auf Geraete-Dateien                        |
|DevicePolicy=value                               |--     |Zugriffs-Policy fuer Geraete-Dateien (strict, closed, auto)|
|Slice=slice_name                                 |--     |Unit einem Slice zuordnen                                  |
|ControlGroupAttribute=attribute value            |--     |Low-Level Control-Group Parameter setzen                   |

*Weight*: default=100. [10-10000]. 100 ist "die Mitte"