如何在 Centos 7 中禁用 CPU 频率缩放

Question

我已经尝试了这里的所有建议如何在 CentOS 6 中禁用 CPU 频率调节？

然而，频率仍然上下变化。即使对于我已经隔离的空闲CPU。

$ grep "cpu MHz" /proc/cpuinfo 
cpu MHz     : 3201.523
cpu MHz     : 2197.091
cpu MHz     : 3575.810
cpu MHz     : 3521.169
cpu MHz     : 1675.158
cpu MHz     : 3559.854
cpu MHz     : 3079.546
cpu MHz     : 3092.115

和

$ grep "cpu MHz" /proc/cpuinfo 
cpu MHz     : 2791.615
cpu MHz     : 3006.516
cpu MHz     : 2203.565
cpu MHz     : 2030.085
cpu MHz     : 1774.537
cpu MHz     : 3591.576
cpu MHz     : 3600.343
cpu MHz     : 3595.899

注意：最后两个CPU是隔离的，所以此时基本空闲。

我尝试过将 BIOS 设置为最大速度和正常速度。我已经尝试了所有的调速器并打开和关闭 intel_pstates。

$ cpupower frequency-info
analyzing CPU 0:
  driver: acpi-cpufreq
  CPUs which run at the same hardware frequency: 0
  CPUs which need to have their frequency coordinated by software: 0
  maximum transition latency: 10.0 us
  hardware limits: 1.20 GHz - 3.60 GHz
  available frequency steps:  3.60 GHz, 3.60 GHz, 3.40 GHz, 3.30 GHz, 3.10 GHz, 2.90 GHz, 2.70 GHz, 2.60 GHz, 2.40 GHz, 2.20 GHz, 2.10 GHz, 1.90 GHz, 1.70 GHz, 1.50 GHz, 1.40 GHz, 1.20 GHz
  available cpufreq governors: conservative userspace powersave ondemand performance schedutil
  current policy: frequency should be within 3.60 GHz and 3.60 GHz.
                  The governor "userspace" may decide which speed to use
                  within this range.
  current CPU frequency: Unable to call hardware
  current CPU frequency: 2.02 GHz (asserted by call to kernel)
  boost state support:
    Supported: yes
    Active: yes

目前的速度通常低于最低速度，但我看到的速度是 4.0 - 4.3 GHz。