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Date: Thu, 2 Dec 2010 17:52:22 +0530
From: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
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Subject: [Qemu-devel] Re: [PATCH] qemu-kvm: response to SIGUSR1 to
	start/stop a VCPU (v2)
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To: Avi Kivity <avi@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>, kvm@vger.kernel.org, Mike Galbraith <efault@gmx.de>, qemu-devel@nongnu.org, Chris Wright <chrisw@sous-sol.org>, Anthony Liguori <aliguori@linux.vnet.ibm.com>

On Thu, Dec 02, 2010 at 05:17:00PM +0530, Srivatsa Vaddagiri wrote:
> Just was wondering how this would work in case of buggy guests. Lets say that a
> guest ran into a AB<->BA deadlock. VCPU0 spins on lock B (held by VCPU1
> currently), while VCPU spins on lock A (held by VCPU0 currently). Both keep
> boosting each other's vruntime, potentially affecting fairtime for other guests
> (to the point of starving them perhaps)?

Guests that exhibit strong spinlock contentions can cause similar symptoms as
well?

- vatsa