Why is idle windows VM using so much CPU?

Posted by Jeff Shattock on Server Fault See other posts from Server Fault or by Jeff Shattock
Published on 2010-05-31T20:07:37Z Indexed on 2010/05/31 20:13 UTC
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kvm

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cpu-usage

I have 2 VMs running as guests on a KVM virtualization platform running on Ubuntu 10.04. One VM is an Ubuntu 10.04 system, the other is a Windows 7 system. When both machines are completely logged out, the Linux machine uses 1% CPU, the Windows one 45-50%, according to top. The graphs in virt-manager seem to back this up. Theres nothing installed on the Win7 image that would be running in the background; its as fresh as can be.

Why is the Windows VM using so much more than the Linux VM, when both are logged out and idling?

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