High CPU usage on Linux host with Windows guest

Fixion · Post by **Fixion** » 17. Feb 2009, 23:43

I'm using a raw partition as a virtual machine. My Linux host reports a constant 100% CPU usage for the VirtualBox process on one of my cores even though the guest OS (windows) is idling. Windows Task Manager reports 10%-20% CPU usage when the VM is idling, which seems high.

My laptop has a 2.2GHz Core 2 Duo and 4 gigs of ram, so I don't think it's a hardware issue. I have 1 gig of ram and 128 megs of video memory assigned to the VM. Does anyone know of a potential solution to this problem?

EDIT: I was using VirtualBox 2.1.4 and I just tried 2.0.6. It behaves in exactly the same manner, except that windows idles around 20%-30% cpu usage

Post by **TerryE** » 18. Feb 2009, 01:27

Search the forum; this is a common Q. The biggest change is to ensure that you are running a non-SMP NT kernel. Don't enable USB unless you require USB support in your guests.

Fixion · Post by **Fixion** » 18. Feb 2009, 17:19

TerryE wrote:Search the forum; this is a common Q. The biggest change is to ensure that you are running a non-SMP NT kernel. Don't enable USB unless you require USB support in your guests.

I've searched this site as well as google, but nothing I've found so far seems to have helped. I've tried VirtualBox-2.1.4, 2.0.6, and the current version of VirtualBox OSE. I've reinstalled the Guest Additions with each one (except OSE), they all still behave the same. My guest says it's using about 10%-20% of the processor, while Vbox on my host has one of my cores pegged at 100% continuously while the VM is running. VMware Player flys comared to VirtualBox when running the same VM.

I'm going to try an older kernel, see how it works.

Post by **sej7278** » 18. Feb 2009, 17:30

Fixion wrote:I've searched this site as well as google, but nothing I've found so far seems to have helped.

well you haven't searched for the correct terms then i guess.

see the thing is its not the linux kernel that's the problem, its the xp kernel, its a longstanding problem, basically xp's acpi kernel does not virtualise well, the kind-of fix is to use the uniprocessor kernel, and also disable usb.

use a different windows such as 2003 or vista is the easier option.

Fixion · Post by **Fixion** » 18. Feb 2009, 18:07

sej7278 wrote:
Fixion wrote:I've searched this site as well as google, but nothing I've found so far seems to have helped.
well you haven't searched for the correct terms then i guess.

You are correct! I searched again including the terms "unprocessor kernel" and found this link, which helped me fix the problem. Now VirtualBox works perfectly! http://forums.virtualbox.org/viewtopic.php?t=7915

Thanks for the help!

Post by **TerryE** » 18. Feb 2009, 23:13

Sorry but I assumed that you would know to search for NTKRNL.