I recently purchased a laptop with a sandy bridge CPU that is supposed to have turbo boost. Is turbo boost supported in 11.04? How can I tell if it's working?
11.04 runs the 2..6.38 kernel which is supposed to work well with Sandy Bridge CPUs.
You can open a terminal and run
grep MHz /proc/cpuinfo. Then open a second terminal tab and run a loop like
while :; do :; done. In the first terminal, run
grep MHz /proc/cpuinfo again. You should see one of the cores has a higher frequency now:
$ grep MHz /proc/cpuinfo cpu MHz : 1600.000 cpu MHz : 1600.000 cpu MHz : 1600.000 cpu MHz : 1600.000 cpu MHz : 1600.000 cpu MHz : 3701.000 cpu MHz : 1600.000 cpu MHz : 1600.000
You can also try powertop and
turbostat from the linux-tools-common package (run
sudo modprobe msr before
sudo turbostat). The SVN version of i7z is supposed to work for Sandry Bridge (and it works for me with a desktop i7).
sudo turbostat for this. The output of
cat /proc/cpuinfo does not always show the real current CPU frequency but instead the maximum non-turbo frequency even when Turbo Boost is enabled and active.
As stated in elmicha's answer, you'll need to load the msr module with
sudo modprobe msr and then run turbostat with
To install turbostat you need to run:
$ sudo apt-get install linux-tools-common linux-tools-generic
(apparently I lack reputation to add this as a comment to @david-gardner post)
Accepted top voted answer doesn't always work
As the second top voted answer pointed out, the top voted and accepted answer sometimes shows the maximum regular frequency.
Alternate CLI methods
Below you can see frequencies for CPU Number 0. To see all CPU's replace
*. The frequency is expressed in MHz with three decimal places. So
1000000 = 1000 MHz = 1 GHz. This Intel Skylake processor is rated to 2.6 GHz or 3.5 GHz with Turbo Boost enabled.
Minimum frequency 800 MHz
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq 800000
Maximum frequency 3500 MHz (3.5 GHz)
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq 3500000
Current frequency 1027.669 MHz (1.028 GHz)
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq 1027669
CPU 0 to 7 Frequency when YouTube loads up
$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq 2754249 2700098 2842167 2700270 1359287 901937 1662780 1731062
4 out of 8 processors are in turbo mode (above 2.6 GHz)
CPU 0 to 7 Frequency when YouTube paused
$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq 808913 800029 800022 800004 800001 800001 800013 800009
All processors are at minimum speed of 800 MHz even though Chrome is running on two screens with 11 tabs open but YouTube paused.
Is Intel Turbo Boost enabled?
Using the terminal you can check if Turbo Boost feature is enabled:
$ cat /sys/devices/system/cpu/intel_pstate/no_turbo 0
This is a double negative; when "no turbo" is off (=0) then Turbo Boost is on.
To disable Turbo Boost use
sudo powers and set the switch
$ echo "1" | sudo tee /sys/devices/system/cpu/intel_pstate/no_turbo 1
1 indicates turbo is now off.
Alternate GUI method using Conky
Other answers mention alternate methods to the basic CLI (Command Line Interface). I like to use Conky to do this. In the example below the Skylake CPU has a regular frequency from 800 MHz to 2600 Mhz. With turbo boost enabled the frequency can jump to 3500 MHz under heavy load.
The .gif sample below starts out by showing frequency fluctuating around 3100 MHz under heavy load when
grep is running on the whole file system. Then the command is issued:
$ echo "1" | sudo tee /sys/devices/system/cpu/intel_pstate/no_turbo
...to shut off turbo boost. Speed drops to fixed speed of 2600 MHz which is the regular maximum speed without turbo.
Then the turbo command is reversed:
$ echo "0" | sudo tee /sys/devices/system/cpu/intel_pstate/no_turbo
...to turn turbo back on and speed jumps above 2600 MHz and fluctuates around 3100 to 3200 MHz again.
Notice how quickly temperature jumps 10 degrees when Turbo is turned on
cpupower is a collection of tools to examine and tune power saving related features of your processor.
cpupower frequency-info can help to get the required info.
# cpupower frequency-info analyzing CPU 0: driver: intel_pstate ... ... current CPU frequency is 2.80 GHz (asserted by call to hardware). boost state support: Supported: yes Active: yes 3000 MHz max turbo 4 active cores 3000 MHz max turbo 3 active cores 3100 MHz max turbo 2 active cores 3100 MHz max turbo 1 active cores
boost state - active confirms what you looking for.
Man page: https://linux.die.net/man/1/cpupower
PS: I know its an old thread but thought this answer is appropriate here and can help someone.