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From: Paolo Bonzini <pbonzini@redhat.com>
To: Samuel Thibault <samuel.thibault@ens-lyon.org>,
	Jan Kiszka <jan.kiszka@web.de>,
	kvm@vger.kernel.org, gleb@kernel.org
Subject: Re: nested KVM slower than QEMU with gnumach guest kernel
Date: Mon, 15 Dec 2014 10:41:23 +0100	[thread overview]
Message-ID: <548EACC3.8090107@redhat.com> (raw)
In-Reply-To: <20141215000916.GC2983@type.youpi.perso.aquilenet.fr>



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

  reply	other threads:[~2014-12-15  9:41 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-11-11 18:55 nested KVM slower than QEMU with gnumach guest kernel Samuel Thibault
2014-11-11 23:42 ` Jan Kiszka
2014-11-16 22:18   ` Samuel Thibault
2014-11-17  6:28     ` Jan Kiszka
2014-11-17  8:50       ` Samuel Thibault
2014-11-24  0:42       ` Samuel Thibault
2014-12-15  0:09       ` Samuel Thibault
2014-12-15  9:41         ` Paolo Bonzini [this message]
2014-11-17  8:58     ` Gleb Natapov
2014-11-17  9:03       ` Samuel Thibault
2014-11-17  9:04         ` Jan Kiszka
2014-11-17  9:10           ` Samuel Thibault
2014-11-17  9:21             ` Gleb Natapov
2014-11-17  9:37               ` Samuel Thibault
2014-11-17  9:38               ` Samuel Thibault
2014-11-23 21:50           ` Samuel Thibault

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