On Sat, 2019-04-06 at 20:26 -0400, Sam Varshavchik wrote:
Tom Horsley writes:
> Here's a weird one I just noticed: I've been using a
> Windows 10 virtual machine to run my tax software.
> I've got it displayed in virt-viewer and all is
> well, then I close the virt-viewer window and
> leave the KVM running. About 5 minutes later I
> see a cpu suddenly pegged at 100%. I run top and see
> that qemu is the culprit. I start virt-viewer
> again, and it goes back to normal.
>
> Anyone else seen this? Why would nobody looking at
> it make it go crazy I wonder?
Because you're using Microsoft Windows 10. Its built-in spyware and
telemetry, that runs all the time and needs to report to Redmond, isn't cost-
free and is pretty hard on the CPU.
True, however QEMU-KVM also consumes significant CPU even when the
Windows guest is paused:
https://bugzilla.redhat.com/show_bug.cgi?id=1638289
poc