NAME

       powerstat - a tool to measure power consumption

SYNOPSIS

       powerstat [options] [delay [count]]

DESCRIPTION

       powerstat  measures the power consumption of a computer that has a battery power source or
       supports the RAPL (Running Average Power Limit) interface.  The output is like vmstat  but
       also  shows  power  consumption statistics.  At the end of a run, powerstat will calculate
       the average, standard deviation and min/max of the gathered data.

       Note that running powerstat as root will provide extra information about process  fork(2),
       exec(2) and exit(2) activity.

OPTIONS

       powerstat options are as follow:

       -a     enable all statistics gathering options, equivalent to -c, -f, -t and -H.

       -b     redo  a  sample measurement if a system is busy, the default for busy is considered
              less than 98% CPU idle. The CPU idle threshold can be altered using the -i option.

       -c     gather CPU C-state activity and show the % time and count in each  C-state  at  the
              end of the run.

       -d delay
              specify  delay  in  seconds before starting, default is 180 seconds when running on
              battery or 0 seconds when using RAPL. This gives the machine time  to  settle  down
              and for the battery readings to stabilize.

       -D     enable  extra  power  stats  showing  all  the  power  domain  power readings. This
              currently only applies to the -R RAPL option.

       -f     compute an average frequency from all on-line CPU cores. Unfortunately a  CPU  core
              is always active to gather any form of stats because powerstat has to be running to
              do so, so these statistics are skewed by this.  It is best to use this option  with
              a  reasonably  large  delay  (more  than  5  seconds) between samples to reduce the
              overhead of powerstat.

       -g     show GPU power readings. Currently just Intel i915 is supported and  one  needs  to
              run powerstat with root privilege to access the kernel i915 /sys debug interface.

       -h     show help.

       -H     show histogram of power measurements.

       -i threshold
              specify  the idle threshold (in % CPU idle) to force a re-sample measurement if the
              CPU is less idle than this level. This option implicitly enables the -b option.

       -n     no headings. Column headings are printed when they scroll off  the  terminal;  this
              option  disables  this  and  allows  one  to  capture the output and parse the data
              without the need to filter out the headings.

       -p     redo a sample measurement if any processes fork(), exec() or exit().

       -r     redo if system is not idle and any processes fork(), exec() or exit(), an alias for
              -p -b.

       -R     read  power statistics from the RAPL (Running Average Power Limit) domains. This is
              supported by recent Linux kernels and Sandybridge and later Intel processors.  This
              only  covers  some  of  the hardware in the machine, such as the processor package,
              DRAM controller, CPU core (power plane 0), graphics uncore (power plane 1)  and  so
              forth, so the readings do not cover the entire machine.
              Because  the  RAPL readings are accurate and available immediately, the start delay
              (-d option) is defaulted to zero seconds.

       -s     this dumps a log of the process fork(), exec() and exit() activity on completion.

       -S     use standard averaging to calculate power consumption instead of using a 120 second
              rolling  average  of  capacity  samples. This is only useful if the battery reports
              just capacity values  and  is  an  alternative  method  of  calculating  the  power
              consumption based on the start and current battery capacity.

       -t     gather  temperatures  from  all the available thermal zones on the device. If there
              are no thermal zones available then nothing will be displayed.

       -z     forcibly ignore zero power rate readings from the battery. Use this to gather other
              statistics  (for example when using -c, -f, -t options) if powerstat cannot measure
              power (not discharging or no RAPL interface).

EXAMPLES

       Measure power with the default of 10 samples with an interval of 10 seconds
               powerstat

       Measure power with 60 samples with an interval of 1 second
               powerstat 1 60

       Measure power and redo sampling if we are not idle  and  we  detect   fork()/exec()/exit()
       activity
               sudo powerstat -r

       Measure power using the Intel RAPL interface:
               powerstat -R

       Measure power using the Intel RAPL interface and show extra RAPL domain power readings and
       power measurement histogram at end of the run
               powerstat -RDH

       Measure power and redo sampling if less that 95% idle
               powerstat -i 95

       Wait  to  settle  for  1  minute  then  measure  power  every  20  seconds  and  show  any
       fork()/exec()/exit() activity at end of the measuring
               powerstat -d 60 -s 20

       Measure   temperature,   CPU  frequencies,  C-states,  power  via  RAPL  domains,  produce
       histograms, don't print repeated headings and measure every 0.5 seconds
               powerstat -tfcRHn 0.5

SEE ALSO

       vmstat(8), powertop(8), power-calibrate(8)

AUTHOR

       powerstat was written by Colin King <colin.king@canonical.com>

       This manual page was written by Colin  King  <colin.king@canonical.com>,  for  the  Ubuntu
       project (but may be used by others).

COPYRIGHT

       Copyright © 2011-2016 Canonical Ltd.
       This  is  free software; see the source for copying conditions.  There is NO warranty; not
       even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

                                         16 August, 2015                             POWERSTAT(8)