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Date: Thu, 5 Mar 2015 00:35:45 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Dave Chinner <david@fromorbit.com>
Cc: Mel Gorman <mgorman@suse.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
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Subject: Re: [regression v4.0-rc1] mm: IPIs from TLB flushes causing
 significant performance degradation.
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* Dave Chinner <david@fromorbit.com> wrote:

> > After going through the series again, I did not spot why there is 
> > a difference. It's functionally similar and I would hate the 
> > theory that this is somehow hardware related due to the use of 
> > bits it takes action on.
> 
> I doubt it's hardware related - I'm testing inside a VM, [...]

That might be significant, I doubt Mel considered KVM's interpretation 
of pte details?

Thanks,

	Ingo