From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: nested KVM slower than QEMU with gnumach guest kernel
Date: Mon, 15 Dec 2014 10:41:23 +0100
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To: Samuel Thibault <samuel.thibault@ens-lyon.org>,
	Jan Kiszka <jan.kiszka@web.de>, kvm@vger.kernel.org,
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On 15/12/2014 01:09, Samuel Thibault wrote:
> Hello,
> 
> Just FTR, it seems that the overhead is due to gnumach somtimes using
> the PIC quite a lot.  It used not to be too much a concern with just
> kvm, but kvm on kvm becomes too expensive for that.  I've fixed gnumach
> into being a lot more reasonable, and the performance issues got away.

Thanks!

Paolo