Visualize the systemd control-group tree to see which processes belong to which units. 21.06.2026 | reading time: 2 min systemd-cgls prints the control-group tree so you can see which processes belong to which systemd units; run it when you need a quick, hierarchical view of the system or a specific user manager. Quick demonstration Try it now: run the command and inspect the ASCII tree; for example, run `sudo systemd-cgls` to view the system manager and `systemd-cgls --user` for the user manager: ```sudo systemd-cgls\nControl group /:\n├─1 /sbin/init\n├─system.slice\n│ ├─sshd.service\n│ │ ├─2345 /usr/sbin/sshd -D\n│ │ └─2346 sshd: worker\n│ └─cron.service\n└─user.slice\n └─user-1000.slice\n └─session-2.scope\n ├─4321 -bash\n └─5678 systemd-cgls``` Practical tips and deeper uses Run `systemd-cgls` as root to see the full system hierarchy, or use the user view to inspect per-login scopes; combine the tree with `ps` or `systemctl status` to find PIDs and unit names, and pipe output to `less -S` to scroll wide trees; remember that on cgroups v2 the layout is unified, so units and slices appear in the same hierarchy. When this helps Use systemd-cgls when a service seems to spawn stray processes, when resource limits apply strangely, or when you need to map a PID back to the owning unit; it is a troubleshooting magnifier, not a performance monitor, so pair it with other tools for live metrics. Related commands to combine Typical workflows pair `systemd-cgls` with `systemctl` to inspect unit definitions and with `systemd-cgtop` or `ps` to measure resource usage; use those together to locate heavy processes and then trace them to their control groups. Wrap-up and next step systemd-cgls gives an immediate, human-readable cgroup tree that helps link processes to units and slices; practice reading the tree on a live system and then dive into cgroup concepts to troubleshoot complex behaviors, and consider formal study for certification through courses like CompTIA Linux+ or LPIC-1 with intensive exam preparation at bitsandbytes.academy. Join Bits & Bytes Academy First class LINUX exam preparation. processes utilities troubleshooting boot-process
