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Date: Fri, 11 May 2012 10:22:30 +0200
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-help] Does qemu-kvm impact realtime performance?
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To: Henri Roosen <henriroosen@domain.hid>
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On 05/10/2012 04:26 PM, Henri Roosen wrote:
> Hi all,
> 
> Does anyone know if running qemu-kvm impacts the realtime Xenomai
> performance of the host system?
> 
> I have a multicore x86 target that runs a Xenomai enabled kernel and a
> realtime application. Next to the realtime application I would like to
> run qemu-kvm (on one of the cores) that runs some non-realtime guest
> os. So I would like to know if qemu-kvm have impact on the
> latencies/jitter of the realtime threads?

I would say it should have no direct impact, we should not expect kvm to
create hard irqs masking sections. However, as usual, running a whole OS
and applications inside another OS probably has a huge impact on cache,
and so should cause more jitter than running xenomai on an idle system.

-- 
					    Gilles.