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From: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
To: Avi Kivity <avi@redhat.com>, Ingo Molnar <mingo@elte.hu>
Cc: peterz@infradead.org, linux-kernel@vger.kernel.org,
        vatsa@linux.vnet.ibm.com, bharata@linux.vnet.ibm.com
Subject: Re: [RFC PATCH 0/4] Gang scheduling in CFS
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Date: Mon, 19 Dec 2011 17:20:46 +0530
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On Mon, 19 Dec 2011 13:44:02 +0200, Avi Kivity <avi@redhat.com> wrote:
> On 12/19/2011 01:23 PM, Ingo Molnar wrote:
> > What's behind this huge speedup? Does ebizzy use user-space 
> > spinlocks perhaps? Could we do something on the user-space side 
> > to get a similar speedup?
> 
> kvm tries to detect spinlocks (by trapping repeated executions of PAUSE)
> and yield to a related vcpu.  It's far from perfect however, and relies
> on the spinlock code using PAUSE.
> 
Avi, is this soft-PLE kind of thing?

Regards
Nikunj