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Date: Thu, 16 Mar 2017 19:49:18 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>
Subject: Re: perf: massive perf_event slowdown between 4.9 and 4.11-rc
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On Thu, Mar 16, 2017 at 01:57:31PM -0400, Vince Weaver wrote:
> On Thu, 16 Mar 2017, Vince Weaver wrote:
> 
> > Anyway all perf_event functionality (especially reads) has become about 
> > 20x slower, at least on Intel machines (haswell and skylake are the only 
> > ones I've tested) sometime between 4.9 and 4.11-rc
> 
> False alarm, I forgot I had debugging (KASAN, etc) turned on in this 
> kernel tree because I had been fuzzing.
> 
> sorry about that.

Ha! no problem.