bionic (1) rapl-info.1.gz

NAME

       rapl-info - get RAPL configurations

SYNPOSIS

       rapl-info [OPTION]...

DESCRIPTION

       Prints out Intel Running Average Power Limit (RAPL) configurations.

       Since  RAPL  does  not implement all capabilities defined in the powercap interface, only a subset of the
       options from powercap-info(1) are available.  Additionally, the -p and -z options are different.

       This software requires an Intel processor (Sandy Bridge or newer), Linux kernel 3.13  or  newer  compiled
       with CONFIG_POWERCAP and CONFIG_INTEL_RAPL enabled, and the intel_rapl kernel module to be loaded.

OPTIONS

       -h, --help
              Prints out the help screen

       -v, --verbose
              Print errors when files are not available

       -p, --package=PACKAGE
              The  package  number (none by default; 0 by default if using -z/--subzone and/or -c/--constraint).
              Ending with a colon prevents output for subzones.  E.g., for package 0, but not subzones:
              -p 0:

       -z, --subzone=SUBZONE
              The package subzone number (none by default)

       -c, --constraint=CONSTRAINT
              The constraint number (none by default)

       All remaining options below are mutually exclusive:

       -n, --nzones
              Print the number of packages found, or the number of subzones found if -p/--package is set

       The following are zone-level arguments (-z/--subzone is optional):

       -j, --z-energy
              Print zone energy counter

       -J, --z-max-energy-range
              Print zone maximum energy counter range

       -e, --z-enabled
              Print zone enable/disabled status

       -x, --z-name
              Print zone name

       The following are constraint-level arguments and require -c/--constraint (-z/--subzone is optional):

       -l, --c-power-limit
              Print constraint power limit

       -s, --c-time-window
              Print constraint time window

       -U, --c-max-power
              Print constraint maximum allowed power

       -y, --c-name
              Print constraint name

EXAMPLES

       Note that -p/--package=0 is used by default when also  specifying  -z/--subzone  and/or  -c/--constraint,
       allowing for simpler commands on single-socket systems.

       rapl-info
              Print all RAPL zones.

       rapl-info -p 0
              Print only package 0, which is usually named package-0.

       rapl-info -p 0 -z 1
              Print package 0, subzone 1, which is usually the uncore or dram subzone of package-0, depending on
              the system.

       rapl-info -p 0 -c 1
              Print package 0, constraint 1, which is usually the short_term constraint for package-0.

       rapl-info -p 0 -j
              Print the energy counter for package 0, which is usually named package-0.

       rapl-info -p 1 -z 0 -c 0 -l
              Print the power limit for package 1, subzone 0, constraint  0,  which  is  usually  the  long_term
              constraint for the core subzone of package-1 (a multi-socket system).

REMARKS

       A package is a zone with constraints.  Subzones are a package's child domains, including power planes.

       If  no  subzone/constraint-specific  outputs  are  requested, all available zones and constraints will be
       shown.

       Energy units: microjoules (uJ)
       Power units: microwatts (uW)
       Time units: microseconds (us)

BUGS

       The following are behavioral quirks due to the kernel interface or abnormalities in some hardware.   They
       are not bugs in rapl-info and should not be reported as such.

       Values  returned  by  the  kernel sometimes lose accuracy from the actual values stored in Model-Specific
       Registers due to integer rounding.  For example, the kernel may return a time window value  of  7812  us,
       when  in  fact  the actual stored value is 7812.5 us.  Writing back a value returned by the kernel, e.g.,
       using rapl-set(1), may cause unexpected changes to its value due to these rounding problems.

       On some systems, the constraint max_power_uw file, e.g., constraint_0_max_power_uw, is known  to  receive
       an  ENODATA  (No  data  available) error from the kernel for subzones.  So even though the file exists, a
       value may not be printed for it.

       It is possible for packages on multi-socket systems to be indexed  out  of  order  by  the  kernel.   For
       example, the package at index 0 (-p 0) could actually be named package-1 while the package at index 1 (-p
       1) is named package-0.

       Report bugs upstream at <https://github.com/powercap/powercap>

FILES

       /sys/devices/virtual/powercap/intel-rapl/*
       /sys/class/powercap/intel-rapl/*

AUTHORS

       Connor Imes <connor.k.imes@gmail.com>

SEE ALSO

       rapl-set(1), powercap-info(1), powercap-set(1)