systemd-cgtop man page

systemd-cgtop — Show top control groups by their resource usage


systemd-cgtop [Options...]


systemd-cgtop shows the top control groups of the local Linux control group hierarchy, ordered by their CPU, memory, or disk I/O load. The display is refreshed in regular intervals (by default every 1s), similar in style to top(1).

If systemd-cgtop is not connected to a tty, no column headers are printed and the default is to only run one iteration. The --iterations argument, if given, is still honored. This mode is suitable for scripting.

Resource usage is only accounted for control groups in the relevant hierarchy, i.e. CPU usage is only accounted for control groups in the cpuacct hierarchy, memory usage only for those in memory and disk I/O usage for those in blkio. If resource monitoring for these resources is required, it is recommended to add the CPUAccounting=1, MemoryAccounting=1 and BlockIOAccounting=1 settings in the unit files in question. See systemd.resource-control(5) for details.

The CPU load value can be between 0 and 100 times the number of processors the system has. For example, if the system has 8 processors, the CPU load value is going to be between 0% and 800%. The number of processors can be found in /proc/cpuinfo.

To emphasize this: unless CPUAccounting=1, MemoryAccounting=1 and BlockIOAccounting=1 are enabled for the services in question, no resource accounting will be available for system services and the data shown by systemd-cgtop will be incomplete.


The following options are understood:

Order by control group path name.
Order by number of tasks in control group (i.e. threads and processes).
Order by CPU load.
Order by memory usage.
Order by disk I/O load.
-b, --batch
Run in "batch" mode: do not accept input and run until the iteration limit set with --iterations is exhausted or until killed. This mode could be useful for sending output from systemd-cgtop to other programs or to a file.
-r, --raw
Format byte counts (as in memory usage and IO metrics) with raw numeric values rather than human-readable numbers.
-n, --iterations=
Perform only this many iterations. A value of 0 indicates that the program should run indefinitely.
-d, --delay=
Specify refresh delay in seconds (or if one of ms, us, min is specified as unit in this time unit).
Maximum control group tree traversal depth. Specifies how deep systemd-cgtop shall traverse the control group hierarchies. If 0 is specified, only the root group is monitored. For 1, only the first level of control groups is monitored, and so on. Defaults to 3.
-h, --help
Print a short help text and exit.
Print a short version string and exit.


systemd-cgtop is an interactive tool and may be controlled via user input using the following keys:

Shows a short help text.
Immediately refresh output.
Terminate the program.
p, t, c, m, i
Sort the control groups by path, number of tasks, CPU load, memory usage, or IO load, respectively.
Toggle between showing CPU time as time or percentage.
+, -
Increase or decrease refresh delay, respectively.

Exit status

On success, 0 is returned, a non-zero failure code otherwise.

See Also

systemd(1), systemctl(1), systemd-cgls(1), systemd.resource-control(5), top(1)

Referenced By

systemd-cgls(1), systemd.directives(7), systemd.index(7).

Explore man page connections for systemd-cgtop(1).