带有 intel_pstate 的 Ubuntu 15.04 - 低当前 CPU 频率

Question

我在台式机上运行 Ubuntu 15.04，配备 6 核 5930K 处理器、msi x99s 主板、32gb 内存、ssd 和 nvidia gtx 980ti。令人惊讶的是，整体系统性能远低于预期，比我的笔记本电脑慢得多。至少乍一看，因为计算机是新的，我没有机会在上面运行大量计算。似乎问题的根源在于新的 intel_pstate 驱动程序保持较低的 CPU 频率。

实际上， cpufreq-info 的输出是

analyzing CPU 0:
  driver: intel_pstate
  CPUs which run at the same hardware frequency: 0
  CPUs which need to have their frequency coordinated by software: 0
  maximum transition latency: 0.97 ms.
  hardware limits: 1.20 GHz - 3.70 GHz
  available cpufreq governors: performance, powersave
  current policy: frequency should be within 3.70 GHz and 3.70 GHz.
                  The governor "performance" may decide which speed to use
                  within this range.
  current CPU frequency is 428 MHz.

任何建议，将 cpu 频率保持如此低的原因将不胜感激。

尽管每个任务的 CPU 使用率非常高，但我的问题似乎与Kubuntu 15.04 非常慢有关， 而且 我的 CPU 会在一段时间后变慢并且无法恢复

虽然我还没有尝试关闭 intel_pstate 选项，因为希望它可以正确配置以解决问题。但是在谷歌搜索几个小时后，希望几乎消失了，盯着配置并与 intel_pstate 斗争。

更新：

sudo cpupower -c all frequency-info 
analyzing CPU 0:
  driver: intel_pstate
  CPUs which run at the same hardware frequency: 0
  CPUs which need to have their frequency coordinated by software: 0
  maximum transition latency: 0.97 ms.
  hardware limits: 1.20 GHz - 3.70 GHz
  available cpufreq governors: performance, powersave
  current policy: frequency should be within 3.70 GHz and 3.70 GHz.
                  The governor "powersave" may decide which speed to use
                  within this range.
  current CPU frequency is 425 MHz (asserted by call to hardware).
  boost state support:
    Supported: yes
    Active: yes

glxinfo | grep render
direct rendering: Yes
OpenGL renderer string: GeForce GTX 980 Ti/PCIe/SSE2
    GL_ARB_compute_variable_group_size, GL_ARB_conditional_render_inverted, 
    GL_KTX_buffer_region, GL_NVX_conditional_render, GL_NVX_gpu_memory_info, 
    GL_NV_conditional_render, GL_NV_conservative_raster, 
    GL_NV_path_rendering, GL_NV_path_rendering_shared_edge, 
    GL_ARB_compute_variable_group_size, GL_ARB_conditional_render_inverted, 
    GL_KTX_buffer_region, GL_NVX_conditional_render, GL_NVX_gpu_memory_info, 
    GL_NV_conditional_render, GL_NV_conservative_raster, 
    GL_NV_path_rendering, GL_NV_path_rendering_shared_edge, 
    GL_EXT_render_snorm, GL_EXT_robustness, GL_EXT_sRGB, 
    GL_NV_blend_equation_advanced_coherent, GL_NV_conditional_render, 
    GL_NV_packed_float_linear, GL_NV_path_rendering, 
    GL_NV_path_rendering_shared_edge, GL_NV_pixel_buffer_object, 
    GL_OES_element_index_uint, GL_OES_fbo_render_mipmap, 

i7z 输出

Cpu speed from cpuinfo 3500.00Mhz
cpuinfo might be wrong if cpufreq is enabled. To guess correctly try estimating via tsc
Linux's inbuilt cpu_khz code emulated now
True Frequency (without accounting Turbo) 3499 MHz
  CPU Multiplier 35x || Bus clock frequency (BCLK) 99.97 MHz

Socket [0] - [physical cores=6, logical cores=12, max online cores ever=6]
  TURBO ENABLED on 6 Cores, Hyper Threading ON
  Max Frequency without considering Turbo 3598.97 MHz (99.97 x [36])
  Max TURBO Multiplier (if Enabled) with 1/2/3/4/5/6 Cores is  37x/37x/36x/36x/36x/36x
  Real Current Frequency 800.24 MHz [99.97 x 8.00] (Max of below)
        Core [core-id]  :Actual Freq (Mult.)      C0%   Halt(C1)%  C3 %   C6 %  Temp      VCore
        Core 1 [0]:       800.24 (8.00x)        2.38     8.1       0    91.4    28      0.7832
        Core 2 [1]:       800.14 (8.00x)        3.94    25.4       0    73.7    32      0.7549
        Core 3 [2]:       799.96 (8.00x)        22.9    76.7       0    18.1    27      0.7939
        Core 4 [3]:       799.93 (8.00x)        3.56    8.44       0    90.7    27      0.7604
        Core 5 [4]:       799.82 (8.00x)        1.11    3.16       0    96.6    28      0.7871
        Core 6 [5]:       799.83 (8.00x)        4.98    12.7       0    86.2    30      0.7421

C0 = Processor running without halting
C1 = Processor running with halts (States >C0 are power saver modes with cores idling)
C3 = Cores running with PLL turned off and core cache turned off
C6, C7 = Everything in C3 + core state saved to last level cache, C7 is deeper than C6

/proc/cpuinfo

grep -E '^model name|^cpu MHz' /proc/cpuinfo
model name  : Intel(R) Core(TM) i7-5930K CPU @ 3.50GHz
cpu MHz     : 422.324

Answer 1

在 grub 配置中禁用 intel_pstate 将当前 CPU 频率精确固定为 3.5GHz，这又有点可疑。而且整体表现依然缓慢。然而，cpufreq-info 报告 acpi-cpufreq 作为驱动程序

lsmod |grep acpi 

什么也没显示并modinfo acpi-cpufreq显示错误。

modprobe acpi-cpufreq 

默默地执行，没有任何效果。

最后，我简单地安装了 Ubuntu 14.04，嘿，一切都快得惊人，即使使用 intel_pstate 也是如此。

fram@hydra:~$ cpufreq-info 
cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009
Report errors and bugs to cpufreq@vger.kernel.org, please.
analyzing CPU 0:
  driver: intel_pstate
  CPUs which run at the same hardware frequency: 0
  CPUs which need to have their frequency coordinated by software: 0
  maximum transition latency: 0.97 ms.
  hardware limits: 1.20 GHz - 3.70 GHz
  available cpufreq governors: performance, powersave
  current policy: frequency should be within 3.70 GHz and 3.70 GHz.
                  The governor "powersave" may decide which speed to use
                  within this range.
  current CPU frequency is 3.51 GHz.

仍然不知道是什么原因，希望更新不会让问题再次出现。