NAME

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

SYNOPSIS

       systemd-cgtop [OPTIONS...] [GROUP]

DESCRIPTION

       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 a control group path is
       specified, shows only the services of the specified control group.

       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 honored. This mode
       is suitable for scripting.

       Resource usage is only accounted for control groups with the appropriate controllers
       turned on: "cpu" controller for CPU usage, "memory" controller for memory usage, and "io"
       controller for disk I/O consumption. If resource monitoring for these resources is
       required, it is recommended to add the CPUAccounting=1, MemoryAccounting=1 and
       IOAccounting=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: unless "CPUAccounting=1", "MemoryAccounting=1", and "IOAccounting=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.

OPTIONS

       The following options are understood:

       -p, --order=path
           Order by control group path name.

       -t, --order=tasks
           Order by number of tasks/processes in the control group.

       -c, --order=cpu
           Order by CPU load.

       -m, --order=memory
           Order by memory usage.

       -i, --order=io
           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 I/O metrics) and CPU time with raw numeric
           values rather than human-readable numbers.

       --cpu=percentage, --cpu=time
           Controls whether the CPU usage is shown as percentage or time. By default, the CPU
           usage is shown as percentage. This setting may also be toggled at runtime by pressing
           the % key.

       -P
           Count only userspace processes instead of all tasks. By default, all tasks are
           counted: each kernel thread and each userspace thread individually. With this setting,
           kernel threads are excluded from the counting and each userspace process only counts
           as one, regardless how many threads it consists of. This setting may also be toggled
           at runtime by pressing the P key. This option may not be combined with -k.

       -k
           Count only userspace processes and kernel threads instead of all tasks. By default,
           all tasks are counted: each kernel thread and each userspace thread individually. With
           this setting, kernel threads are included in the counting and each userspace process
           only counts as on one, regardless how many threads it consists of. This setting may
           also be toggled at runtime by pressing the k key. This option may not be combined with
           -P.

       --recursive=
           Controls whether the number of processes shown for a control group shall include all
           processes that are contained in any of the child control groups as well. Takes a
           boolean argument, which defaults to "yes". If enabled, the processes in child control
           groups are included, if disabled, only the processes in the control group itself are
           counted. This setting may also be toggled at runtime by pressing the r key. Note that
           this setting only applies to process counting, i.e. when the -P or -k options are
           used. It has not effect if all tasks are counted, in which case the counting is always
           recursive.

       -n, --iterations=
           Perform only this many iterations. A value of 0 indicates that the program should run
           indefinitely.

       -1
           A shortcut for --iterations=1.

       -d, --delay=
           Specify refresh delay in seconds (or if one of "ms", "us", "min" is specified as unit
           in this time unit). This setting may also be increased and decreased at runtime by
           pressing the + and - keys.

       --depth=
           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.

       -M MACHINE, --machine=MACHINE
           Limit control groups shown to the part corresponding to the container MACHINE. This
           option may not be used when a control group path is specified.

       -h, --help
           Print a short help text and exit.

       --version
           Print a short version string and exit.

KEYS

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

       h
           Shows a short help text.

       Space
           Immediately refresh output.

       q
           Terminate the program.

       p, t, c, m, i
           Sort the control groups by path, number of tasks, CPU load, memory usage, or I/O load,
           respectively. This setting may also be controlled using the --order= command line
           switch.

       %
           Toggle between showing CPU time as time or percentage. This setting may also be
           controlled using the --cpu= command line switch.

       +, -
           Increase or decrease refresh delay, respectively. This setting may also be controlled
           using the --delay= command line switch.

       P
           Toggle between counting all tasks, or only userspace processes. This setting may also
           be controlled using the -P command line switch (see above).

       k
           Toggle between counting all tasks, or only userspace processes and kernel threads.
           This setting may also be controlled using the -k command line switch (see above).

       r
           Toggle between recursively including or excluding processes in child control groups in
           control group process counts. This setting may also be controlled using the
           --recursive= command line switch. This key is not available if all tasks are counted,
           it is only available if processes are counted, as enabled with the P or k keys.

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)