CPU Scaling in Gutsy

mertle · 10-27-2007, 02:55 PM

I recently upgraded to Kubuntu Gutsy from Feisty and CPU scaling no longer works. I have a Pentium M 1.60 gHz processor on a Dell 9300 laptop and it's currently stuck at 800 mHz at all times. Speedstep is enabled in the BIOS and I've tried manually editing the scaling files, following numerous CPU scaling HOWTOS, loading/unloading modules by hand, and cpufrequtils... nada. The min and max freq are the same, no matter what I do.

This seems to be an often posted problem, but I've yet to find anything that works to solve it. I know this is a known bug in the Gutsy kernel, but has anyone found a workaround? Some people ound a temporary solution which only works until the next reboot, but even I haven't had that much success.

Will rolling back to an older kernel fix this until a solution is found, or just muck me up further?

$ cpufreq-info:

Code:

cpufrequtils 002: cpufreq-info (C) Dominik Brodowski 2004-2006
Report errors and bugs to linux@brodo.de, please.
analyzing CPU 0:
  driver: acpi-cpufreq
  CPUs which need to switch frequency at the same time: 0
  hardware limits: 800 MHz - 1.60 GHz
  available frequency steps: 1.60 GHz, 1.33 GHz, 1.07 GHz, 800 MHz
  available cpufreq governors: userspace, powersave, ondemand, conservative, performance
  current policy: frequency should be within 800 MHz and 800 MHz.
                  The governor "ondemand" may decide which speed to use
                  within this range.
  current CPU frequency is 800 MHz (asserted by call to hardware).

/etc/modules:

Code:

# /etc/modules: kernel modules to load at boot time.
#
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.

fuse
lp
sbp2
i8k
acpi-cpufreq
cpufreq_conservative
cpufreq_ondemand
cpufreq_powersave
cpufreq_stats
cpufreq_userspace

NOTE: Never needed anything after i8k in Feisty, but I added those just in case.

$ lsmod:

Code:

Module                  Size  Used by
speedstep_lib           6404  0
snd_hda_intel          22680  0
snd_hda_codec         249232  1 snd_hda_intel
hsfusbcd2              66216  0
hsfmc97sis             68248  0
hsfmc97ati             66840  0
hsfmc97ali             73504  0
hsfmc97via             69408  0
hsfmc97ich             71576  0
hsfpcibasic3          109608  0
hsfpcibasic2           67608  0
hsfserial              24612  8 hsfusbcd2,hsfmc97sis,hsfmc97ati,hsfmc97ali,hsfmc97via,hsfmc97ich,hsfpcibasic3,hsfpcibasic2
hsfengine            1295244  9 hsfusbcd2,hsfmc97sis,hsfmc97ati,hsfmc97ali,hsfmc97via,hsfmc97ich,hsfpcibasic3,hsfpcibasic2,hsfserial
hsfosspec             105704  13 hsfusbcd2,hsfmc97sis,hsfmc97ati,hsfmc97ali,hsfmc97via,hsfmc97ich,hsfpcibasic3,hsfpcibasic2,hsfserial,hsfengine
hsfsoar                93904  7 hsfusbcd2,hsfmc97sis,hsfmc97ati,hsfmc97ali,hsfmc97via,hsfmc97ich,hsfpcibasic2
ipv6                  273892  8
af_packet              24840  2
radeon                125472  2
drm                    83348  3 radeon
rfcomm                 42136  2
l2cap                  26240  11 rfcomm
bluetooth              57060  4 rfcomm,l2cap
vboxdrv                60208  0
ppdev                  10244  0
sbs                    19592  0
video                  18060  0
ac                      6148  0
container               5504  0
dock                   10656  0
button                  8976  0
battery                11012  0
cpufreq_userspace       5280  0
cpufreq_stats           7232  0
cpufreq_powersave       2688  0
cpufreq_ondemand        9612  1
cpufreq_conservative     8072  0
acpi_cpufreq           10568  0
freq_table              5792  3 cpufreq_stats,cpufreq_ondemand,acpi_cpufreq
i8k                     7320  0
sbp2                   24072  0
parport_pc             37412  0
lp                     12580  0
parport                37448  3 ppdev,parport_pc,lp
snd_intel8x0           34972  1
snd_ac97_codec        100644  1 snd_intel8x0
ac97_bus                3200  1 snd_ac97_codec
snd_usb_audio          81024  1
snd_pcm_oss            44672  0
snd_mixer_oss          17664  1 snd_pcm_oss
snd_seq_dummy           4740  0
snd_seq_oss            33152  0
snd_pcm                80388  6 snd_hda_intel,snd_hda_codec,snd_intel8x0,snd_ac97_codec,snd_usb_audio,snd_pcm_oss
snd_usb_lib            17920  1 snd_usb_audio
snd_seq_midi            9600  0
snd_seq_midi_event      8448  2 snd_seq_oss,snd_seq_midi
ipw2200               149320  0
snd_rawmidi            25728  2 snd_usb_lib,snd_seq_midi
ieee80211              35656  1 ipw2200
snd_seq                53232  6 snd_seq_dummy,snd_seq_oss,snd_seq_midi,snd_seq_midi_event
snd_timer              24324  2 snd_pcm,snd_seq
ieee80211_crypt         7040  1 ieee80211
joydev                 11328  0
snd_seq_device          9228  5 snd_seq_dummy,snd_seq_oss,snd_seq_midi,snd_rawmidi,snd_seq
pcmcia                 41388  0
snd_hwdep              10244  1 snd_usb_audio
snd                    54660  18 snd_hda_intel,snd_hda_codec,snd_intel8x0,snd_ac97_codec,snd_usb_audio,snd_pcm_oss,snd_mixer_oss,snd_seq_oss,snd_pcm,snd_rawmidi,snd_seq,snd_timer,snd_seq_device,snd_hwdep
soundcore               8800  1 snd
snd_page_alloc         11400  3 snd_hda_intel,snd_intel8x0,snd_pcm
sdhci                  18828  0
pcspkr                  4224  0
mmc_core               28420  1 sdhci
yenta_socket           27532  1
rsrc_nonstatic         14080  1 yenta_socket
pcmcia_core            40980  3 pcmcia,yenta_socket,rsrc_nonstatic
psmouse                39952  0
iTCO_wdt               11940  0
iTCO_vendor_support     4868  1 iTCO_wdt
serio_raw               8068  0
intel_agp              25620  0
agpgart                35016  2 drm,intel_agp
shpchp                 34580  0
pci_hotplug            32704  1 shpchp
evdev                  11136  5
ext3                  133896  3
jbd                    60456  1 ext3
mbcache                 9732  1 ext3
sg                     36764  0
sr_mod                 17828  0
cdrom                  37536  1 sr_mod
sd_mod                 30336  5
ahci                   23300  0
ata_piix               17540  4
ohci1394               36528  0
ieee1394               96312  2 sbp2,ohci1394
ata_generic             8452  0
libata                125168  3 ahci,ata_piix,ata_generic
scsi_mod              147084  5 sbp2,sg,sr_mod,sd_mod,libata
b44                    28300  0
mii                     6528  1 b44
ehci_hcd               36492  0
uhci_hcd               26640  0
usbcore               138632  7 hsfusbcd2,hsfosspec,snd_usb_audio,snd_usb_lib,ehci_hcd,uhci_hcd
thermal                14344  0
processor              32072  2 acpi_cpufreq,thermal
fan                     5764  0
fuse                   47124  1
apparmor               40728  0
commoncap               8320  1 apparmor

$ dmesg:

[ Would have posted but I reached the posting char limit. If needed, will post follow-up ]

biophysics · 10-28-2007, 12:39 PM

can you post me:

$ sudo cat /sys/devices/cpu/cpu0/cpufreq/scaling_governor

$ sudo cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors

mertle · 10-28-2007, 01:24 PM

$ sudo cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
ondemand

$ sudo cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors
userspace powersave ondemand conservative performance

mertle · 10-29-2007, 08:25 PM

UPDATE: Nothing's fixed, but I found that it's not a kernel bug like I had thought. I rolled back to 2.6.20-15, the one I used prior to upgrade, and still no scaling.

systemdown · 11-13-2007, 07:49 PM

I'm running Gutsy 2.6.22-14 kernel. This works for me (at least temporarily) - it won't normally let me write to anything in the /sys/devices/system/cpu/cpu0/cpufreq path unless I'm *actually* root, not just 'sudo'. I have a 2GHz T7300 Centrino Duo, which 'ondemand' likes to run at 800MHz most of the time!

user@localhost> cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
800000
user@localhost> cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
ondemand

Trying to set scaling_governor (also applies to scaling_setspeed):

user@localhost> sudo echo "userspace" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
bash: scaling_setspeed: Permission denied

When root:

user@localhost> sudo su -
#root@localhost> echo "userspace" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
#root@localhost> cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
userspace

Then I can happily set the CPU frequency:

#root@localhost> echo "2000000" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed
#root@localhost> cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed
2000000

The CPU Frequency Monitor widget in my Application Panel under Gnome now tells me I'm running at a constant 2GHz, and obviously checking the scaling_cur_freq tells me that as well.

This is really useful when running Virtual Machines, because if I run under 'ondemand' scaling, I get a very fast clock in the host VM due to difference in expected and actual CPU clock speed.

samiscooking · 11-17-2007, 04:35 PM

Hi, I've a turion X2 , when I set "conservative" governor my cpu runs at 800 Mhz (forever) and when I set "ondemand" it runs at 1600 Mhz (forever). I simply I don't know why..(noob :-) )