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> cpu frequency selectors how to change them?, cpufreq-selector command not working
helikaon
 Posted: Oct 26 2011, 06:21 PM
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Hi guys,
just asking if someone tried to change cpu frequency selectors on your SL?
I just tried and i fail at it.

Problem is, i noticed while on running my laptop on battery, my both cores ran at max speed (2.1ghz), so i tried them to scale them down as i was used to do on SL 5x.
But it does not work ...

CODE

[root@orionis ~]# cpufreq-selector -g conservative
No cpufreq support



but it should work, because my kernel has those modules:
CODE

[root@orionis ~]# cat /boot/config-2.6.32-131.17.1.el6.x86_64 | grep -i cpu

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



and i can even load them manually:
CODE

modprobe "cpufreq_ondemand"
modprobe "cpufreq_powersave"
modprobe cpufreq_conservative

[root@orionis ~]# lsmod | grep -i cpufreq*
cpufreq_powersave       1130  0
cpufreq_ondemand       10382  0
freq_table              4847  1 cpufreq_ondemand
cpufreq_conservative     7108  0



So it's there, but still the loading utility fails (and my core happily wolf down on battery) blink.gif




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AndrewSerk
 Posted: Oct 27 2011, 12:45 AM
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Hello helikaon,

Not sure if this is the issue, but I have the acpi_cpufreq and cpufreq_ondemand modules loaded and cat /proc/cpuinfo shows they are throttled.

Hope this helps,
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helikaon
 Posted: Oct 27 2011, 04:16 AM
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QUOTE (AndrewSerk @ Oct 27 2011, 12:45 AM)
Hello helikaon,

Not sure if this is the issue, but I have the acpi_cpufreq and cpufreq_ondemand modules loaded and cat /proc/cpuinfo shows they are throttled.

Hope this helps,


Thx for reply, it's kind of strange,
i didnt have the "acpi_cpufreq" loaded and even after i loaded it via modprobe, both my CPU cores still run at full speed and actually I had no *cpufreq* modules loaded at all at the beginning and i loaded them via modprobe - as shown at first post..
.
CODE

[root@orionis ~]# cat /proc/cpuinfo
processor       : 0                
vendor_id       : GenuineIntel    
cpu family      : 6                
model           : 23              
model name      : Intel(R) Core(TM)2 Duo CPU     T8100  @ 2.10GHz
stepping        : 6                                              
cpu MHz         : 2094.832                                      
cache size      : 3072 KB                                        
physical id     : 0                                      


After i manually loaded the "acpi_cpufreq" i'm able now to run the
"[root@orionis ~]# cpufreq-selector -g powersave"

but with no impact at all, the cores still at max speed ...

I'll try reboot my laptop and see. I'm on conference, so i've been suspending to RAM only and not shutting down...


Ok,
i rebooted laptop with power cord plugged in and with it plugged off, to try to activate appropriate power modes (as stated in 'system settings -> power management' in my KDE), but no change.

Both cores runs at full speed and 'lsmod' still show no '*cpufreq*' kernel modules loaded at all ...

Can anyone else please check if

"lsmod | grep cpufreq"

show him appropriate modules loaded?

Thank You smile.gif


This post has been edited by helikaon: Oct 27 2011, 04:53 AM


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U308
 Posted: Oct 27 2011, 06:10 AM
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Have you tried it the easy way ? i.e. adding the cpu freq. scaling monitor to panel.

user posted image
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helikaon
 Posted: Oct 27 2011, 10:49 AM
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Ok guys, thx for tips, solved.
As usuall, it was 'small missing thingie' - i've installed the SL as 'base' system without anything and then been adding piece by piece the rest of OS packages.

Apparently, there is new OS service in SL 6, so i had to do:

CODE

yum install cpuspeed
[root@orionis ~]# chkconfig --list | grep -i cpu
cpuspeed        0:off   1:on    2:on    3:on    4:on    5:on    6:off

service cpuspeed start



now my CPU cores scaled back to nice base 800MHz and my battery is happy smile.gif

Note (frome TUV docs):
Procedure 3.2. Enabling a CPUfreq Governor

1.
If a specific governor is not listed as available for your CPU, use modprobe to enable the governor you wish to use. For example, if the "conservative" governor is not available for your CPU, use the following command:
modprobe cpufreq_conservative

2.
Once a governor is listed as available for your CPU (via 'lsmod' command), you can enable it using:
echo "conservative" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
Also note, if you have more CPU cores, repeat it for each core - so here it is 'cpu0', in case of dual core CPU, replace the 'core0' with 'core1' in the line. This is needed, because you can have different governor for each CPU core.


cheers,

This post has been edited by helikaon: Oct 27 2011, 11:11 AM


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