PDA

View Full Version : [ubuntu] CPU usage really high with no running process



dman535
December 15th, 2008, 02:52 PM
When I view system resources tab in the system monitor my CPU is showing between 50% and 80% - spikes to 100 with no significant applications running. When I go to the process tab I see gnome system monitor at 5% and an occasional xorg at 20% - but nothing to indicate a process that is maxing out the CPU. I do notice that this O/S seems to run slower than XP did on my laptop (Dell D600)

Any ideas on what is wrong?

Thanks

Derek.-

howefield
December 15th, 2008, 02:55 PM
run the top command in a terminal, might give you some clues.

Michael.Godawski
December 15th, 2008, 03:02 PM
hi dman535,

pls run top as suggested above.
You are not alone with this high cpu usage behavior, as it seems:
http://ubuntuforums.org/showthread.php?t=804201

This might be related to your graphic card. Please post the output from

sudo lshw -C display

dman535
December 15th, 2008, 03:14 PM
run the top command in a terminal, might give you some clues.

top - 09:12:27 up 1:43, 2 users, load average: 0.71, 0.54, 0.47
Tasks: 120 total, 2 running, 118 sleeping, 0 stopped, 0 zombie
Cpu(s): 41.2%us, 3.7%sy, 0.0%ni, 54.8%id, 0.0%wa, 0.3%hi, 0.0%si, 0.0%st
Mem: 1033308k total, 866676k used, 166632k free, 56516k buffers
Swap: 1646620k total, 0k used, 1646620k free, 379532k cached

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
4894 root 20 0 219m 116m 14m R 29.9 11.5 13:39.44 Xorg
9396 derek 20 0 250m 116m 26m S 12.6 11.5 2:18.02 firefox
5309 derek 20 0 22172 14m 5980 S 1.3 1.4 0:40.08 compiz.real
5648 derek 20 0 59692 35m 17m S 0.7 3.5 0:23.40 pidgin
10628 derek 20 0 97728 22m 12m S 0.7 2.2 0:00.82 gnome-terminal
10652 derek 20 0 2416 1152 884 R 0.7 0.1 0:00.28 top
1 root 20 0 3056 1888 564 S 0.0 0.2 0:01.64 init

sdennie
December 15th, 2008, 03:15 PM
My guess is the thing that is causing the very high CPU usage is the gnome-system-monitor itself. This has been a bug since the new system monitor was introduced in Hardy and the larger the system monitor window, the more CPU it will use. As suggested above, use top or htop in a terminal instead of gnome-system-monitor to get more accurate CPU usage.

dman535
December 15th, 2008, 03:16 PM
hi dman535,

pls run top as suggested above.
You are not alone with this high cpu usage behavior, as it seems:
http://ubuntuforums.org/showthread.php?t=804201

This might be related to your graphic card. Please post the output from

sudo lshw -C display

*-display UNCLAIMED
description: VGA compatible controller
product: Radeon RV250 [Mobility FireGL 9000]
vendor: ATI Technologies Inc
physical id: 0
bus info: pci@0000:01:00.0
version: 01
width: 32 bits
clock: 66MHz
capabilities: agp agp-2.0 pm bus_master vga_palette cap_list
configuration: latency=32 mingnt=8

Michael.Godawski
December 15th, 2008, 03:20 PM
vor so true :neutral:
https://bugs.launchpad.net/ubuntu/+source/gnome-system-monitor/+bug/187383

dman535
December 15th, 2008, 05:51 PM
I do notice that when things like the root password prompt comes up and the whole display is greyed out - it seems like the machine struggles. Should I be doing something different with the display driver?

D.-

tkawa6
December 15th, 2008, 06:17 PM
4894 root 20 0 219m 116m 14m R 29.9 11.5 13:39.44 Xorg
9396 derek 20 0 250m 116m 26m S 12.6 11.5 2:18.02 firefox
5309 derek 20 0 22172 14m 5980 S 1.3 1.4 0:40.08 compiz.real

I think compiz and desktop effects is what's causing xorg to eat up your system recourses. I have the same laptop and the same issues until I switched off desktop effects and stayed away from compiz. My xorg CPU usage went from averaging on the 30%-60% (when watching videos) to 2.5%-20%.