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)