systemd-cgtop(1)


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 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.

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) 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.

   -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)





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