Since kernel 3.3 or so, RAPL is also exposed through `/sys/devices/virtual/powercap/intel-rapl/*/energy_uj` in micro-joules (if not, `modprobe intel_rapl`). So if you want to do a quick power measurement, it can be done using just POSIX sh (root required):
# in milli-watt (1000 = 1W) because shell arithmetic doesn't do floating point
while true; do
LAST_MJ=$MJ
MJ=$(cat /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/energy_uj)
echo $(((MJ - LAST_MJ) / 1000))
sleep 1
done
Despite the powercap name being intel-rapl, the powercap interface is also available on AMD machines.
For a more detailed reading on several more metrics about the CPU, I think pcm[1] may be a better tool (it's a successor to the Intel Power Gadget the project was forked from). Though, it only works on Intel CPU.
For a more detailed reading on several more metrics about the CPU, I think pcm[1] may be a better tool (it's a successor to the Intel Power Gadget the project was forked from). Though, it only works on Intel CPU.
[1]: https://github.com/intel/pcm