public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
* mistake about the cpufreq?
@ 2011-07-01 20:00 俞颐超
  2011-07-02  1:17 ` 俞颐超
  0 siblings, 1 reply; 3+ messages in thread
From: 俞颐超 @ 2011-07-01 20:00 UTC (permalink / raw)
  To: linux-kernel

The following is what I get when I run the command in
/sys/devices/system/cpu/cpu0/cpufreq

$ sudo grep "" *
affected_cpus:0
bios_limit:800000
cpuinfo_cur_freq:2800000
cpuinfo_max_freq:2801000
cpuinfo_min_freq:800000
cpuinfo_transition_latency:10000
related_cpus:0 1
scaling_available_frequencies:2801000 2800000 2133000 1600000 800000
scaling_available_governors:conservative ondemand userspace powersave
performance
scaling_cur_freq:800000
scaling_driver:acpi-cpufreq
scaling_governor:performance
scaling_max_freq:800000
scaling_min_freq:800000
scaling_setspeed:<unsupported>

The problem is basically the scalings is different from cpuinfos. It
appears when I unplug the power and still there when I have repluged
the power.
Does any know what probably the problem is and where can I look for
more detail information.

some basic info about my computer

$ uname -a
Linux yuyichao-PC 2.6.39-ARCH #1 SMP PREEMPT Mon Jun 27 21:26:22 CEST
2011 x86_64 Intel(R) Core(TM)2 Duo CPU T9600 @ 2.80GHz GenuineIntel
GNU/Linux
(The kernel version should be 2.6.39.2)


Thanks.

Yichao

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: mistake about the cpufreq?
  2011-07-01 20:00 mistake about the cpufreq? 俞颐超
@ 2011-07-02  1:17 ` 俞颐超
  2011-07-05 17:55   ` Matthew Garrett
  0 siblings, 1 reply; 3+ messages in thread
From: 俞颐超 @ 2011-07-02  1:17 UTC (permalink / raw)
  To: linux-kernel, cpufreq

On Fri, Jul 1, 2011 at 4:00 PM, 俞颐超 <yyc1992@gmail.com> wrote:
> The following is what I get when I run the command in
> /sys/devices/system/cpu/cpu0/cpufreq
>
> $ sudo grep "" *
> affected_cpus:0
> bios_limit:800000
> cpuinfo_cur_freq:2800000
> cpuinfo_max_freq:2801000
> cpuinfo_min_freq:800000
> cpuinfo_transition_latency:10000
> related_cpus:0 1
> scaling_available_frequencies:2801000 2800000 2133000 1600000 800000
> scaling_available_governors:conservative ondemand userspace powersave
> performance
> scaling_cur_freq:800000
> scaling_driver:acpi-cpufreq
> scaling_governor:performance
> scaling_max_freq:800000
> scaling_min_freq:800000
> scaling_setspeed:<unsupported>
>
> The problem is basically the scalings is different from cpuinfos. It
> appears when I unplug the power and still there when I have repluged
> the power.
> Does any know what probably the problem is and where can I look for
> more detail information.
>
> some basic info about my computer
>
> $ uname -a
> Linux yuyichao-PC 2.6.39-ARCH #1 SMP PREEMPT Mon Jun 27 21:26:22 CEST
> 2011 x86_64 Intel(R) Core(TM)2 Duo CPU T9600 @ 2.80GHz GenuineIntel
> GNU/Linux
> (The kernel version should be 2.6.39.2)
>
>
> Thanks.
>
> Yichao
>

So after reading the files in cpu-freq/, I saw it was mentioned in
user-guide.txt that the scaling_ ones is what the kernel thinks the
freq is and cpuinfo is the actual freq.
y can these two be different?

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: mistake about the cpufreq?
  2011-07-02  1:17 ` 俞颐超
@ 2011-07-05 17:55   ` Matthew Garrett
  0 siblings, 0 replies; 3+ messages in thread
From: Matthew Garrett @ 2011-07-05 17:55 UTC (permalink / raw)
  To: 俞颐超; +Cc: linux-kernel, cpufreq

On Fri, Jul 01, 2011 at 09:17:08PM -0400, 俞颐超 wrote:

> So after reading the files in cpu-freq/, I saw it was mentioned in
> user-guide.txt that the scaling_ ones is what the kernel thinks the
> freq is and cpuinfo is the actual freq.
> y can these two be different?

Many systems don't have independently clockable cores. In that case the 
cpu will run at the speed of the highest clocked core.

-- 
Matthew Garrett | mjg59@srcf.ucam.org

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2011-07-05 17:55 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2011-07-01 20:00 mistake about the cpufreq? 俞颐超
2011-07-02  1:17 ` 俞颐超
2011-07-05 17:55   ` Matthew Garrett

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox