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CPU usage/load on host [message #24168]

Sun, 02 December 2007 07:58

esoterik
Messages: 5
Registered: December 2007

Junior Member

Running webmin on the host node (centos 4.5) shows me a 98.7% CPU usage consistently while running one idle ubuntu 7.10 minimal VPS with extremely limited resources,

I didn't see anything about this in the documentation, was wondering if this high load/cpu usage (by the init process) was normal on the host node? Pretty new to all this stuff so if you have any suggestions assume I know next to nothing Smile

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Re: CPU usage/load on host [message #24191 is a reply to message #24168]

Sun, 02 December 2007 21:40

Vasily Tarasov
Messages: 1345
Registered: January 2006

Senior Member

Hello esoterik,

This high CPU usage is definetly caused not by OpenVZ: stop the only VE that runs on your node and check that CPU usage is still high (if your VE is in fact idle).

Then try to figure out which process on HN intensively uses CPU.

HTH,
Vasily.

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Re: CPU usage/load on host [message #24197 is a reply to message #24191]

Mon, 03 December 2007 03:17

esoterik
Messages: 5
Registered: December 2007

Junior Member

after a bit of playing around:

running top shows 99% cpu usage for the init process. If I run --cpulimit 20 top shows init running at 20% of the cpu, still giving me a very high load. Running a second VE with a limit of 20 gives me a total cpu usage of 20%, I would have expected it to jump to 40.

viewing from within the 1 idle VE top shows me the same thing. Im wondering if I have some setting wrong, but expectation was that an idle VE on an idle HN would have very low CPU usage, and that would ramp up when programs began to run.

Is there some setting/configuration I need to check, or a place that I can see what is causing this init process to actively run as high as I will allow it.

top from within an idle VE: (--cpulimit 20)

top - 08:19:22 up 5 min, 0 users, load average: 0.99, 0.69, 0.31
Tasks: 4 total, 3 running, 1 sleeping, 0 stopped, 0 zombie
Cpu(s): 58.8%us, 41.2%sy, 0.0%ni, 0.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 1048576k total, 3124k used, 1045452k free, 0k buffers
Swap: 0k total, 0k used, 0k free, 0k cached

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1 root 25 0 1756 680 592 R 20.0 0.1 1:07.69 init
18210 root 15 0 1772 408 300 R 0.0 0.0 0:00.00 vzctl
18211 root 15 0 2900 1572 1244 S 0.0 0.1 0:00.00 bash
18225 root 15 0 2368 1092 880 R 0.0 0.1 0:00.00 top

I thought I should add I have nothing else installed on this system, its a brand new centos4.5 install with only the openvz modifications to get it to run installed.

Shutting down the only running VE the system returns to near 0% cpu usage and load drops down to near 0 as well. So I know its something to do with OpenVZ, or at least something to do with a VE.

[Updated on: Mon, 03 December 2007 03:20]

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Re: CPU usage/load on host [message #24200 is a reply to message #24197]

Mon, 03 December 2007 05:20

Vasily Tarasov
Messages: 1345
Registered: January 2006

Senior Member

OK, from my point of veiw, VE's init process eats all your CPU. Where did you get this VE? I mean is it based on precreated template (which?) or was template created by vzpkg?

Thank you,
Vasily

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Re: CPU usage/load on host [message #24202 is a reply to message #24200]

Mon, 03 December 2007 08:05

esoterik
Messages: 5
Registered: December 2007

Junior Member

Ive tried a few precreated templates off the openvz site, specifically debian-i386-minimal, ubuntu-i386-minimal, debian-4-i386-default..

yes, youre correct its the VE's init process.

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Re: CPU usage/load on host [message #24249 is a reply to message #24202]

Mon, 03 December 2007 15:05

Vasily Tarasov
Messages: 1345
Registered: January 2006

Senior Member

_All_ VEs (based debian-i386-minimal, ubuntu-i386-minimal, debian-4-i386-default...) reveal the same beahaviour (init eats all CPU)?
If it's so it is really interesting. What distribution do you use? What is your OpenVZ kernel version (uname -a)?

Thank you.

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Re: CPU usage/load on host [message #24294 is a reply to message #24249]

Mon, 03 December 2007 18:10

esoterik
Messages: 5
Registered: December 2007

Junior Member

2.6.18-8.1.15.el5.028stab049.1 #1 SMP Thu Nov 8 16:23:12 MSK 2007 i686 athlon i386 GNU/Linux

Which is interesting because I have a 3700+ AMD single core 64 bit processor. Wondering if the SMP version is what is causing it and I really need the UP version.

# cd /etc/yum.repos.d
# wget http://download.openvz.org/openvz.repo
# yum install ovzkernel

were my steps to install the kernel.

RE debian based distros, yes this is the case. I installed a test fedora core 5 template and it did not have the CPU usage problems, but all debian based distributions did.

If I need to swap out the kernel modules, how would I go about forcing the UP version, seeing as install ovzkernel with no parameters didnt work!

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Re: CPU usage/load on host [message #24492 is a reply to message #24168]

Wed, 05 December 2007 15:20

swindmill
Messages: 57
Registered: April 2007

Member

I am also experiencing the same issue but with a patched 2.6.22 kernel under Ubuntu 7.10 32-bit.

When I create a VE using the ubuntu 7.10 minimal 32-bit precreated template available at http://download.openvz.org and start it, init eats 100% CPU and won't shutdown properly using vzctl. I have to kill -9 the process from the HN to shut down the VE.

I downloaded the debian 4.0 minimal template from debian.systs.org and don't have the same issue, so it seems to be a problem with the template. Unfortunately, my knowledge of the underlying processes isn't great enough for me to debug/fix the problem.

Should we not be offering broken templates for download from openvz.org?

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