CPU runs at 85% constantly with no programs running

[Susan Cragin]

I just updated my system 17-Feb-2010 12:40 EST US and suddenly CPU usage is near 100% all the time with no programs running.
I have no idea what's wrong. It had been working fine until a minute ago.
I have standard Ubuntu Studio.
I also have Fluxbox installed. I tried booting into that, but there was no difference.
I use wicd rather than network-manager-gnome (because of fluxbox)

Hope this has helped.

ProblemType: Bug
Architecture: i386
Date: Wed Feb 17 12:38:42 2010
DistroRelease: Ubuntu 10.04
InstallationMedia: Error: [Errno 13] Permission denied: '/var/log/installer/media-info'
Package: linux-rt 2.6.31.10.12
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.31-10.153-rt
SourcePackage: linux-meta-rt
Uname: Linux 2.6.31-10-rt i686

[Susan Cragin (susancragin)]

I ran my own dmesg log.

[Susan Cragin (susancragin)]

This may not be a linux-rt problem because I tried installing linux-mint which has a generic kernel, and got the same thing.
So I re-installed Ubuntu Studio totally clean, just now, and the problem is the same.
Both CPU cores running at 85 to 90%, with no programs running.

[Susan Cragin (susancragin)]

It's syslog that's hogging all the CPU. See the attached screenshot showing the "top" command.
I checked out the other bugs and decided to upgrade from the linux-rt kernel to the generic kernel, thinking that might solve my problem.
Sadly, that produced a massive slowdown of the system. I guess the kernel has to be in place before syslog is upgraded. Anyway, corruption followed and I had to re-install my system from scratch.
I have (for the present) uninstalled the syslog program (and ubuntu-minimal). I'll probably try re-installing them after I get a kernel update.

[Alessio Igor Bogani (abogani)]

Hi,

Could you check this bug against -realtime kernel available on my PPA, please?

This is the PPA:
https://launchpad.net/~abogani/+archive/ppa

This is the install instructions:
https://launchpad.net/+help/soyuz/ppa-sources-list.html

Please consider that on this kernel closed drivers don't works so you should disable these first.

As general rule you should disable all driver with "Proprietary" license in System -> Administration -> Hardware Drivers

Thanks a lot!

[Susan Cragin (susancragin)]

Kernel appears to work, and to solve the problem.
Hooray.
I have not tested it extensively, but am running a newly installed system with syslog in place, and everything is taking the proper amount of CPU.
As per your instructions, did not load NVIDIA drivers. My screen resolution is 800x600 and the system cannot detect my monitor properly, which I assume was to be expected.

[Alessio Igor Bogani (abogani)]

Susan,

You are right it is expected.

In any case some users report that nvidia closed driver works on -realtime too. If you try this please be sure to have an updated system (that is "dpkg -l linux-realtime" must report 2.6.31.12.22) .

Thanks!

[Alessio Igor Bogani (abogani)]

Review requested and obtained from Ubuntu Kernel Team:
https://lists.ubuntu.com/archives/kernel-team/2010-May/010543.html

Packages are available on this PPA:
https://launchpad.net/~abogani/+archive/broken/+packages