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Subject: Re: [PATCH V3]hrtimer: Fix a performance regression by disable
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From: Mike Galbraith <bitbucket@online.de>
To: Ethan Zhao <ethan.kernel@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@kernel.org>,
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Date: Thu, 12 Dec 2013 15:42:02 +0100
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On Thu, 2013-12-12 at 22:14 +0800, Ethan Zhao wrote: 
> Mike,
>     it seems the IPI issue got root cause (cpu hardware errata ) now ?
> I only catch some pieces of the mails, is that to say the crazy horse
> made by Intel will wake up unexpected, and eat too much reschedule
> IPI, then the horse got hotter, performance down, and so the fix would
> be a 'CFLUSH' to all the buggy CPU, is that right ?

You're mixing a couple different issues together, but yeah, close
enough.  The barking amazonian tree guppy is being saved as we speak.

-Mike