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How do I troubleshoot High CPU ?

Posted: 12. May 2010, 12:41
by linickx
Hello,

I have VBox 3.1.8 running on OSX 10.6.3, I have a Centos 5.4 Guest running the latest additions.

The Guest reports a very minimal load, but the process on my host is between 50% -> 100% causing my macbook to run hot.

This screenshot here .... shows top from both Guest & Host, does anyone have any idea on how to diagnose/troubleshoot the issue?

Cheers,
Nick

Re: How do I troubleshoot High CPU ?

Posted: 12. May 2010, 19:10
by thiagomz
Same problem here ! With windows xp as guest... 20-30% with guest idle...

Re: How do I troubleshoot High CPU ?

Posted: 13. May 2010, 04:26
by jester
And I'm having the same problem as well; I have VirtualBox 3.1.8 on Snow Leopard, with the 3.1.8 Guest Additions; running Ubuntu 10.04 as a guest (with appropriate memory allocations, etc.), I find that even with the guest OS almost totally idle, VirtualBox is eating up 70-80% of the Mac's CPU.

I'd welcome any suggestions for how to fix this. I'm not trying to run a bunch of guests at the same time, but I do need this guest to run without maxing out the host machine.

Re: How do I troubleshoot High CPU ?

Posted: 13. May 2010, 10:05
by linickx
I've found a ticket ... http://www.virtualbox.org/ticket/1884... the last comment is worrying...
Please direct us if you have a better approach to getting resolution in this issue. Most of us are willing to help by providing anything that is needed, as long as we have guidance as to what that is. Your condescending attitude is not very helpful.

Re: How do I troubleshoot High CPU ?

Posted: 13. May 2010, 11:03
by fixedwheel
linickx wrote:I have a Centos 5.4 Guest
for CentOS, Red Hat EL, Oracle EL and fedora guests: read the manual => http://www.virtualbox.org/manual/ch11.html#id2989109

short answer: add divider=10 to the kernel parms in /boot/grub/grub.conf (you can do a search here, lots of examples already given)

Re: How do I troubleshoot High CPU ?

Posted: 13. May 2010, 16:07
by togume
Hi everyone. I've been trying to get some traction on this for a while. This has been happening for me with Ubuntu as a host, and WinXP and Win7. It happens only when I open a browser with semi-intense javascript, such as FireFox w/Gmail.

I also started a new ticket after a moderator asked me to do so if this was still happening on the latest version of VB: http://www.virtualbox.org/ticket/6204

Re: How do I troubleshoot High CPU ?

Posted: 14. May 2010, 01:47
by ukchucktown
I've always noticed higher CPU usages in VirtualBox compared to VMware Fusion. I generally use Fusion to compare VB performance. My Windows Server 2008 VM idles at 32%. I'm not sure it's really a problem. VB has always consumed more CPU than Fusion in my environment. I cloned my VDI files and tested them in Fusion. Here are my benchmarks from top using VB 3.1.8 and Fusion 3.0.2...

Windows Server 2008 VM with 2 gig of memory allocated
VirtualBox: 32% CPU usage when idle; Fusion: 20% CPU usage when idle

Kubuntu 9.10 VM with 1 gig of memory allocated
VirtualBox: 16% when idle; Fusion: 10% when idle

It's not scientific but it's clear to me VB taxes the CPU a little more than Fusion. For now I opted to run Windows in Fusion until the next release of VB.

Cheers, UK

Re: How do I troubleshoot High CPU ?

Posted: 14. May 2010, 10:03
by linickx
fixedwheel wrote:short answer: add divider=10 to the kernel parms in /boot/grub/grub.conf
Solved my particular issue, thanks fixedwheel; however some tools or troubleshooting steps for non Redhat/Fedora/CentOS in the Wiki might be a good idea for others :)

Cheers,
Nick