From mboxrd@z Thu Jan  1 00:00:00 1970
From: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Subject: Re: [PATCH] qemu-kvm: response to SIGUSR1 to start/stop a VCPU (v2)
Date: Thu, 2 Dec 2010 17:52:22 +0530
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Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>,
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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