Summary:
Ubuntu 10.04 hangs when the CPU scaling governor is set to "ondemand", "conservative", or "userspace" at 1000 MHz and 900 MHz. Other freqs don't hang.
Motherboard: Jetway NF77-N1G6-LF
CPU: VIA Nano processor L2200@1600MHz
Ubuntu installer: Ubuntu 10.04.1 64-bit alternate
Test setup:
- Install Ubuntu 10.04.1 64-bit from an alternate CD or an alternate USB stick.
- As soon as you reach the login screen, quickly press CTRL+ALT+F6 to go to a terminal, then quickly type "sudo chmod -x /etc/init.d/ondemand". The quickly type "sudo reboot" to reboot the computer. This will disable the ondemand script from changing the cpu governor on the next boot.
- On the next boot, log in normally, then update all packages from the Update Manager, and reboot if necessary.
- Launch a Terminal window. All test cmds will be executed from this directory:
$ cd /sys/devices/system/cpu/cpu0/cpufreq
- Open a 2nd Terminal window and execute this so you can watch the CPU freq.
$ watch -n0 "cat /proc/cpuinfo"
Test:
- Check the available and current governor, the available freqs, and the scaling driver.
$ cat scaling_available_governors
conservative ondemand userspace powersave performance
$ cat scaling_governor
performance
$ cat scaling_available_frequencies
1600000 1400000 1300000 1200000 1100000 1000000 900000 800000
$ cat scaling_driver
acpi-cpufreq
- Try powersave. The CPU drops to 800 MHz. No hang.
$ echo -n powersave | sudo tee scaling_governor
- Try ondemand. Ubuntu hangs after I press enter.
$ echo -n ondemand | sudo tee scaling_governor
- Reboot, then try conservative. Ubuntu hangs a moment after I press enter. I observed the CPU freq dropping to 1400 MHz, then 1300 MHz, 1200 MHz, 1100 MHz, then hang.
$ echo -n conservative | sudo tee scaling_governor
- Reboot, then try userspace. No hang at this point. CPU freq is 1600 MHz.
$ echo -n userspace | sudo tee scaling_governor
- Manually change the CPU freq. These changes don't hang. The CPU freq is correctly changed to the specified freq.
$ echo -n 1400000 | sudo tee scaling_setspeed
$ echo -n 1300000 | sudo tee scaling_setspeed
$ echo -n 1200000 | sudo tee scaling_setspeed
$ echo -n 1100000 | sudo tee scaling_setspeed
- Now try 1000 MHz. This hangs instantly.
$ echo -n 1000000 | sudo tee scaling_setspeed
- Reboot, try 900 MHz. This hangs instantly.
$ echo -n 900000 | sudo tee scaling_setspeed
- Reboot, try 800 MHz. CPU freq changed to 800 Mhz. No hang.
$ echo -n 800000 | sudo tee scaling_setspeed
- If the CPU is already at 800 MHz, "ondemand" sometimes doesn't hang instantly. My guess is that the hang occurs when a process in the background pushes the CPU to 1600 MHz, then ondemand hangs when it tries to quickly scale the CPU freq back down to 800 MHz.
- I have a different motherboard that also has a VIA Nano L2200 CPU. The board is a VIA VB8001. There is no problem with ondemand on that board because "/sys/devices/system/cpu/cpu0/cpufreq" doesn't even exist. I have no idea why.
---
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24.
ApportVersion: 1.23-0ubuntu4
Architecture: amd64
ArecordDevices:
**** List of CAPTURE Hardware Devices ****
card 0: VT82xx [HDA VIA VT82xx], device 0: VT1708B Analog [VT1708B Analog]
Subdevices: 2/2
Subdevice #0: subdevice #0
Subdevice #1: subdevice #1
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/controlC0: lee 1434 F.... xfce4-volumed
lee 1440 F.... pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
Card hw:0 'VT82xx'/'HDA VIA VT82xx at 0xdfff8000 irq 68'
Mixer name : 'VIA VT1708B 8-Ch'
Components : 'HDA:1106e721,16f307f5,00100100'
Controls : 27
Simple ctrls : 15
DistroRelease: Ubuntu 11.10
HibernationDevice: RESUME=UUID=af61867e-a9e1-4201-94ca-bcb9d713183a
InstallationMedia: Xubuntu 11.04 "Natty Narwhal" - Release amd64 (20110426.1)
IwConfig:
lo no wireless extensions.
eth0 no wireless extensions.
Lsusb:
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 002: ID 045e:0095 Microsoft Corp. IntelliMouse Explorer 4.0 (IntelliPoint)
MachineType: VIA Technologies Ltd. VX800
Package: linux (not installed)
ProcEnviron:
PATH=(custom, no user)
LANG=en_US.UTF-8
SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.0.0-17-generic root=UUID=5b5aaf54-85cf-4eb6-848c-8745288f5ce7 ro quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 3.0.0-17.30-generic 3.0.22
RelatedPackageVersions:
linux-restricted-modules-3.0.0-17-generic N/A
linux-backports-modules-3.0.0-17-generic N/A
linux-firmware 1.60
RfKill:
Tags: oneiric
Uname: Linux 3.0.0-17-generic x86_64
UpgradeStatus: Upgraded to oneiric on 2012-04-01 (0 days ago)
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare
dmi.bios.date: 12/03/2008
dmi.bios.vendor: Phoenix Technologies, LTD
dmi.bios.version: 6.00 PG
dmi.board.name: VX800
dmi.board.vendor: VIA Technologies Ltd.
dmi.board.version: 1.0
dmi.chassis.type: 3
dmi.chassis.vendor: VIA Technologies Ltd.
dmi.chassis.version: VX800
dmi.modalias: dmi:bvnPhoenixTechnologies,LTD:bvr6.00PG:bd12/03/2008:svnVIATechnologiesLtd.:pnVX800:pvr1.0:rvnVIATechnologiesLtd.:rnVX800:rvr1.0:cvnVIATechnologiesLtd.:ct3:cvrVX800:
dmi.product.name: VX800
dmi.product.version: 1.0
dmi.sys.vendor: VIA Technologies Ltd.
This bug is missing log files that will aid in dianosing the problem. From a terminal window please run:
apport-collect 805205
and then change the status of the bug back to 'New'.
If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.
This change has been made by an automated script, maintained by the Ubuntu Kernel Team.