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Date: Thu, 5 Mar 2015 00:35:45 +0100
From: Ingo Molnar <mingo@kernel.org>
Subject: Re: [regression v4.0-rc1] mm: IPIs from TLB flushes causing
 significant performance degradation.
Message-ID: <20150304233544.GA24733@gmail.com>
References: <20150303014733.GL18360@dastard>
 <CA+55aFw+7V9DfxBA2_DhMNrEQOkvdwjFFga5Y67-a6yVeAz+NQ@mail.gmail.com>
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 <20150303113437.GR4251@dastard>
 <20150303134346.GO3087@suse.de>
 <20150303213353.GS4251@dastard>
 <20150304200046.GP3087@suse.de>
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To: Dave Chinner <david@fromorbit.com>
Cc: Mel Gorman <mgorman@suse.de>, Linus Torvalds <torvalds@linux-foundation.org>, Andrew Morton <akpm@linux-foundation.org>, Matt B <jackdachef@gmail.com>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, linux-mm <linux-mm@kvack.org>, xfs@oss.sgi.com


* 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

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