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Date: Tue, 12 Aug 2008 13:17:46 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] AMD 100% CPU bug; patch available?
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To: qemu-devel@nongnu.org

David Barrett wrote:
> Can anybody confirm that qemu works on an AMD processor with a Linux 
> host and Linux guest (ideally Ubuntu 8.04 in both cases) without using 
> 100% CPU?  (qemu process on the host uses 100% CPU despite all 
> processes on the guest being idle.)
>
> Or is there a known bug that qemu with a Ubuntu guest always uses 100% 
> CPU on AMD Ubuntu hosts?  If so, is there a patch or workaround for it?
>
> I don't know this for certain, but it's the only pattern I can see: 
> I've run qemu on a bunch of laptops and servers over the past 12 
> months -- often with the exact same image and exact same commands -- 
> and some hosts see the guest VM use limited CPU, and others a solid 
> 100%.  This seems to be the case whether or not -kernel-kqemu is used.

Do you still see this if you use -no-kqemu?

Regards,

Anthony Liguori