kwin and Xorg sporadically consuming CPU

**euromonkey** · 13-Aug-2010, 07:51

Hi all,

I am using openSUSE 11.2 x64 with KDE 4.3.5.

I am experiencing sudden, sporadic drops in performance due to the kwin and Xorg processes suddenly consuming large amounts of CPU for a few minutes (maybe 30-40% each) before dropping back to normal (1-3% each). I am seeing this using top.

Any suggestions what I can do to find the cause of and correct this?

Many thanks!

**twelveeighty** · 13-Aug-2010, 12:18

In most cases, you can fix these by using the NVIDIA/ATI/INTEL drivers for your graphics card. What graphics card do you have and did you install a proprietary driver?

**euromonkey** · 13-Aug-2010, 14:09

I have an NVIDIA Quadro FX 2700M and I did install the proprietary driver.

From dmesg:
[ 9.814874] nvidia: module license 'NVIDIA' taints kernel.
[ 10.251726] NVRM: loading NVIDIA UNIX x86_64 Kernel Module 195.36.15 Fri Mar 12 00:29:13 PST 2010

Here is my xorg.conf:

# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings: version 1.0 (buildmeister@builder58) Fri Mar 12 02:13:46 PST 2010

Section "ServerLayout"
Identifier "Layout0"
Screen 0 "Screen0" 0 0
InputDevice "Keyboard0" "CoreKeyboard"
InputDevice "Mouse0" "CorePointer"
Option "Xinerama" "0"
EndSection

Section "Files"
EndSection

Section "InputDevice"

# generated from default
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/psaux"
Option "Emulate3Buttons" "no"
Option "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"

# generated from default
Identifier "Keyboard0"
Driver "kbd"
EndSection

Section "Monitor"

# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor0"
VendorName "Unknown"
ModelName "IQT HDIT22W DSUB"
HorizSync 31.0 - 82.0
VertRefresh 56.0 - 76.0
Option "DPMS"
EndSection

Section "Device"
Identifier "Device0"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "Quadro FX 2700M"
Option "UseEdidDpi" "FALSE"
Option "DPI" "96 x 96"
EndSection

Section "Screen"

# Removed Option "TwinViewXineramaInfoOrder" "CRT-0"
# Removed Option "metamodes" "CRT: nvidia-auto-select +1920+0, DFP: nvidia-auto-select +0+0"
# Removed Option "metamodes" "CRT: 1920x1080 +0+0, DFP-0: nvidia-auto-select +1920+0, DFP-1: NULL"
Identifier "Screen0"
Device "Device0"
Monitor "Monitor0"
DefaultDepth 24
Option "TwinView" "1"
Option "TwinViewXineramaInfoOrder" "DFP-1"
Option "metamodes" "CRT: nvidia-auto-select +0+0, DFP-1: nvidia-auto-select +1920+0"
SubSection "Display"
Depth 24
EndSubSection
EndSection

**deano_ferrari** · 13-Aug-2010, 14:27

Maybe this is a powermizer issue? (I don't have nvidia hardware, so only a guess on my part, but it does cause problems for some users when dynamically switching between clock frequencies).

nVidia PowerMizer powersaving/cooling in Linux (updated) | Nobody was Born with Linux Knowledge

NVidia Powermizer - how to tweak ??

**deano_ferrari** · 13-Aug-2010, 14:28

Edit: Double post.

**duncreg** · 13-Aug-2010, 21:54

I believe this might be the "resolved" bug https://bugzilla.novell.com/show_bug.cgi?id=584919 that it seems you're still experiencing and I am also on OpenSuse 11.3.

**euromonkey** · 16-Aug-2010, 02:40

Thanks for the ideas. I think it is less likely it is the bug since I don't have KDE 4.4. I am investigating the PowerMizer possibility first and will report back once that process is complete.

**euromonkey** · 19-Aug-2010, 02:37

I updated my NVIDIA driver and KDE to 4.4.4 but things got catastrophically worse with applications like firefox for example churning away at 100%. I downgraded my NVIDIA driver back to 195.36.15 from 256.44 and everything went back to normal with no issues with kwin, xorg or anything else.

It seems the 256.44 kernel module caused all sorts of issues. I'm not sure then if it was the upgrade to KDE 4.4.4 or the NVIDIA reinstall that improved things but I'll take it.

It takes a bit of getting used to in Linux how a simple upgrade can really clobber your system!

**euromonkey** · 24-Aug-2010, 02:06

This has now been narrowed down a bit. When the symptoms occur (i.e. Xorg/kwin consuming CPU and load average shooting up), if I remove AC power to the laptop, as soon as openSUSE displays the notification that power has been removed, top shows the CPU usage return to normal. After plugging the power back it things continue normally for a few minutes before it occurs again. This is repeatable and reproducible.

Clearly this is something to-do with power management or fan/clock control etc. Any ideas what it might be and what I can do about it other than the NVIDIA settings? I'm still working on getting those to work.

Many thanks!