I’ve started monitoring cpu frequencies on my processors (dual Xeon e5-2670) and it is a bit strange. Most of the ways used for monitoring it does not show fluctuations of frequency. FOr example:
lscpu | grep MHz
gives me:
CPU MHz: 2599.985
CPU max MHz: 3300,0000
CPU min MHz: 1200,0000
no matter on the workload, current MHz are stuck at 2600 (or 2599.985 in this case). Same with
grep \"cpu MHz\" /proc/cpuinfo
and similar commands.
The only command that shows variance that I found is :
cpupower frequency-info
Which gives me something like:
analyzing CPU 0:
driver: intel_pstate
CPUs which run at the same hardware frequency: Not Available
CPUs which need to have their frequency coordinated by software: Not Available
maximum transition latency: Cannot determine or is not supported.
hardware limits: 1.20 GHz - 3.30 GHz
available cpufreq governors: performance
current policy: frequency should be within 1.20 GHz and 3.30 GHz.
The governor "powersave" may decide which speed to use
within this range.
current CPU frequency: Unable to call hardware
current CPU frequency: 3.15 GHz (asserted by call to kernel)
boost state support:
Supported: yes
Active: yes
25500 MHz max turbo 4 active cores
25500 MHz max turbo 3 active cores
25500 MHz max turbo 2 active cores
25500 MHz max turbo 1 active cores
which seems a bit wrong (and shows only one of CPUs), but at least I’m seeing some frequency changes in current CPU frequency (for example when I use
watch cpupower frequency-info
).
Any ideas why I’m getting such results?
Just in case here’s my system spec:
System: Host: domek1 Kernel: 4.12.14-lp150.12.7-default x86_64 bits: 64
Desktop: Xfce 4.12.4 Distro: openSUSE Leap 15.0
Machine: Device: desktop Mobo: ASRock model: EP2C602 serial: N/A
UEFI: American Megatrends v: P1.80 date: 12/09/2013
CPU(s): 2 Octa core Intel Xeon E5-2670 0s (-HT-MCP-SMP-)
speed/max: 2599/3300 MHz
Graphics: Card-1: NVIDIA GM204 [GeForce GTX 980]
Card-2: NVIDIA GP106 [GeForce GTX 1060 3GB]
Display Server: x11 (X.Org 1.19.6 ) driver: nvidia
Resolution: 1920x1080@60.00hz, 2560x1440@59.95hz
OpenGL: renderer: GeForce GTX 980/PCIe/SSE2
version: 4.5.0 NVIDIA 390.77
Network: Card: Intel 82574L Gigabit Network Connection driver: e1000e
You need to use the switches