Tjyylli

My Linux computer with custom kernel configuration seems slow. Even make menuconfig of Linux kernel is as slow as I can see redrawing of the menu. When I run cpupower frequency-info, frequency is below 150 MHz. But the minimum frequency on this CPU is 500 MHz. This is an Intel® Pentium® quad core processor N3540 (up to 2.66 GHz). I have never seen something like this.

Why is the frequency so low? I did not touched cpu-freq configuration since boot. The computer is resumed from sleep-to-ram.

I can set the frequency manually but it is fixed at (about) 64 MHz.

$ LANG= cpupower 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:  Cannot determine or is not supported.

  hardware limits: 500 MHz - 2.67 GHz

  available cpufreq governors: performance powersave

  current policy: frequency should be within 500 MHz and 1.07 GHz.

                  The governor "powersave" may decide which speed to use

                  within this range.

  current CPU frequency: Unable to call hardware

  current CPU frequency: 129 MHz (asserted by call to kernel)

  boost state support:

    Supported: yes

    Active: yes

lscpu output is created when the computer is OK.

$ LANG= lscpu

Architecture:        x86_64

CPU op-mode(s):      32-bit, 64-bit

Byte Order:          Little Endian

Address sizes:       36 bits physical, 48 bits virtual

CPU(s):              4

On-line CPU(s) list: 0-3

Thread(s) per core:  1

Core(s) per socket:  4

Socket(s):           1

Vendor ID:           GenuineIntel

CPU family:          6

Model:               55

Model name:          Intel(R) Pentium(R) CPU  N3540  @ 2.16GHz

Stepping:            8

CPU MHz:             618.821

CPU max MHz:         2665.6001

CPU min MHz:         499.8000

BogoMIPS:            4331.60

Virtualization:      VT-x

L1d cache:           24K

L1i cache:           32K

L2 cache:            1024K

Flags:               fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 movbe popcnt tsc_deadline_timer rdrand lahf_lm 3dnowprefetch epb pti tpr_shadow vnmi flexpriority ept vpid tsc_adjust smep erms dtherm ida arat

The CPU frequency can be outside the limits, because the processor itself will slow
itself down if the load is light enough, regardless of the parameters.

You should only worry if the CPU frequency does not go up very quickly when
there is actual work to do. But if it does not, below are some possibilities:

• A battery issue, when the battery is really low and not charging.




• General OS confusion that may be fixed by unplugging the power cord and plugging
  it back in again (or reboot).




• Issues with CPU cooling, which may happen even when the laptop case is not
  even warm. So check sensors.




• A serious problem requiring a repair-shop.