Re: [gentoo-user] Core i7 M620 power management problem

[Paul Hartman]

On Wed, Dec 29, 2010 at 2:51 PM, Bill Longman <bill.longman@×××××.com> wrote:
>> Yeah, the cpufreq utils show all the relevant information. I use the
>> acpi-cpufreq driver and when I didn't use it nothing happened. cpufreq-aperf
>> shows each CPU at 1.2GHz. I'll look at the EIST in BIOS, too. Thanks for the
>> pointers.
>
> Here's an interesting item:
>
> 12:41:00# cat /sys/devices/system/cpu/cpu0/cpufreq/bios_limit
> 1199000
>
> which sort of jives with the "asserted by call to hardware" in the
> cpufreq-info section:
> analyzing CPU 3:
>   driver: acpi-cpufreq
>   CPUs which run at the same hardware frequency: 0 1 2 3
>   CPUs which need to have their frequency coordinated by software: 3
>   maximum transition latency: 10.0 us.
>   hardware limits: 1.20 GHz - 2.67 GHz
>   available frequency steps: 2.67 GHz, 2.67 GHz, 2.53 GHz, 2.40 GHz, 2.27
> GHz, 2.13 GHz, 2.00 GHz, 1.87 GHz, 1.73 GHz, 1.60 GHz, 1.47 GHz, 1.33 GHz,
> 1.20 GHz
>   available cpufreq governors: conservative, ondemand, userspace, powersave,
> performance
>   current policy: frequency should be within 1.20 GHz and 1.20 GHz.
>                   The governor "performance" may decide which speed to use
>                   within this range.
>   current CPU frequency is 1.20 GHz (asserted by call to hardware).
>   cpufreq stats: 2.67 GHz:0.25%, 2.67 GHz:0.01%, 2.53 GHz:0.01%, 2.40
> GHz:0.01%, 2.27 GHz:0.01%, 2.13 GHz:0.01%, 2.00 GHz:0.01%, 1.87 GHz:0.01%,
> 1.73 GHz:0.01%, 1.60 GHz:0.01%, 1.47 GHz:0.01%, 1.33 GHz:0.01%, 1.20
> GHz:99.61%  (28)
>
> So, why are there micro-spikes of higher frequencies in the above stats? The
> stats section says there are only five transitions.

I ran cpufreq-info on my i7 920, and everything looked normal for mine
compared to yours. And I have tens of thousands of transitions on each
CPU (currently at 8 days uptime)

Can you use cpufreq-set to change the max limit or lock it to a higher
speed? If it works, that's a good sign... if it gets changed back
maybe some userspace powersaving program is messing with it. Like
gnome/KDE or something. If you boot to console and don't start X, does
this problem still happen? I wonder if it happens in X maybe the few
times at greater speeds happened before X loaded. Just a WAG. :)

For example, on my laptop (not an i7, but an old Athlon from 2004),
the KDE laptop powersaving stuff does not work properly, it either
locks me at slowest speed, or highest speed, or... but I think in my
case it's related to the corrupt DSDT, crappy BIOS and complete
inability for it to read the battery state most of the time... It
doesn't know if it's plugged in or on battery, or how much battery
life is left, or it thinks 84% remains and that number never changes
(until laptop suddenly dies without warning). Of course all of that
works perfectly fine in Windows on the same machine...

In my kernel config on my i7, in the cpufreq sections I have this:

#
# CPU Frequency scaling
#
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_TABLE=y
# CONFIG_CPU_FREQ_DEBUG is not set
CONFIG_CPU_FREQ_STAT=y
# CONFIG_CPU_FREQ_STAT_DETAILS is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set
CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
# CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set
CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=y
CONFIG_CPU_FREQ_GOV_USERSPACE=y
CONFIG_CPU_FREQ_GOV_ONDEMAND=y
CONFIG_CPU_FREQ_GOV_CONSERVATIVE=y

#
# CPUFreq processor drivers
#
# CONFIG_X86_PCC_CPUFREQ is not set
CONFIG_X86_ACPI_CPUFREQ=y
# CONFIG_X86_POWERNOW_K8 is not set
# CONFIG_X86_SPEEDSTEP_CENTRINO is not set
# CONFIG_X86_P4_CLOCKMOD is not set


I can send you my entire .config if you want to compare.